* suspected or confirmed fever (fever ≥38.5℃) within 72 hours before enrollment, or axillary body temperature ≥37.3℃ on the day of enrollment; * diastolic blood pressure ≥ 100 mmhg and/or systolic blood pressure ≥ 160 mmhg without or after drug control; * have a history of previous infection with new coronary pneumonia or a positive nucleic acid test history; * those who currently suffer from the following diseases: 1.thrombocytopenia, any coagulation disorder, or receiving anticoagulant therapy, etc.; 2.history of congenital or acquired immunodeficiency or autoimmune disease; asplenia, or history of spleen surgery, trauma, or treatment with immunomodulatory agents within 6 months, such as: immunosuppressive doses of glucocorticoids (dose reference: equivalent or prednisone 20mg/day for more than one week); or monoclonal antibody; or thymosin; or interferon, etc.; 3.those suffering from acute infectious diseases or using antipyretic/analgesic/antiallergic drugs within 3 days before enrollment, or acute exacerbation of chronic diseases; 4.cancer patients (except basal cell carcinoma) who have been off treatment for less than 6 months; 5.serious chronic diseases such as congenital heart disease, severe liver and kidney disease, severe diabetes (with complications) that may interfere with the conduct or completion of the study; 6.active tuberculosis, viral hepatitis patients with obvious liver damage (excluding virus carriers) and/or hiv-positive or syphilis-specific antibody-positive; * previous history of severe hypersensitivity to any vaccine, or severe hypersensitivity history to any component of the investigational vaccine, including aluminum preparations, such as: anaphylactic shock, allergic laryngeal edema, anaphylactoid purpura, thrombocytopenic purpura, dyspnea, vascular nerve edema, etc.; * administer subunit vaccine and inactivated vaccine within 14 days before the trial vaccine, and receive live attenuated vaccine within 28 days; * received blood or blood-related products, including immune globulin, within 3 months prior to screening; or planned use within 6 months after study initiation to full vaccination; * in addition to completing 2 doses of inactivated novel coronavirus vaccine within the past 3-9 months, participating in other covid-19 related clinical trials; * pregnant women (including women of childbearing age with positive urine pregnancy test); * investigators believe that the presence of any disease or condition in the subject may put the subject at unacceptable risk; the subject cannot meet protocol requirements; interfere with the assessment of vaccine response, etc.

* suspected or confirmed fever (fever ≥38.5℃) within 72 hours before enrollment, or axillary body temperature ≥37.3℃ on the day of enrollment; * diastolic blood pressure ≥ 100 mmhg and/or systolic blood pressure ≥ 160 mmhg without or after drug control; * have a history of previous infection with new coronary pneumonia or a positive nucleic acid test history; * those who currently suffer from the following diseases: 1.thrombocytopenia, any coagulation disorder, or receiving anticoagulant therapy, etc.; 2.history of congenital or acquired immunodeficiency or autoimmune disease; asplenia, or history of spleen surgery, trauma, or treatment with immunomodulatory agents within 6 months, such as: immunosuppressive doses of glucocorticoids (dose reference: equivalent or prednisone 20mg/day for more than one week); or monoclonal antibody; or thymosin; or interferon, etc.; 3.those suffering from acute infectious diseases or using antipyretic/analgesic/antiallergic drugs within 3 days before enrollment, or acute exacerbation of chronic diseases; 4.cancer patients (except basal cell carcinoma) who have been off treatment for less than 6 months; 5.serious chronic diseases such as congenital heart disease, severe liver and kidney disease, severe diabetes (with complications) that may interfere with the conduct or completion of the study; 6.active tuberculosis, viral hepatitis patients with obvious liver damage (excluding virus carriers) and/or hiv-positive or syphilis-specific antibody-positive; * previous history of severe hypersensitivity to any vaccine, or severe hypersensitivity history to any component of the investigational vaccine, including aluminum preparations, such as: anaphylactic shock, allergic laryngeal edema, anaphylactoid purpura, thrombocytopenic purpura, dyspnea, vascular nerve edema, etc.; * administer subunit vaccine and inactivated vaccine within 14 days before the trial vaccine, and receive live attenuated vaccine within 28 days; * received blood or blood-related products, including immune globulin, within 3 months prior to screening; or planned use within 6 months after study initiation to full vaccination; * in addition to completing 2 doses of inactivated novel coronavirus vaccine within the past 3-9 months, participating in other covid-19 related clinical trials; * pregnant women (including women of childbearing age with positive urine pregnancy test); * investigators believe that the presence of any disease or condition in the subject may put the subject at unacceptable risk; the subject cannot meet protocol requirements; interfere with the assessment of vaccine response, etc.

suspected or confirmed fever (fever ≥38.5℃) within 72 hours before enrollment, or axillary body temperature ≥37.3℃ on the day of enrollment; diastolic blood pressure ≥ 100 mmhg and/or systolic blood pressure ≥ 160 mmhg without or after drug control; have a history of previous infection with new coronary pneumonia or a positive nucleic acid test history; those who currently suffer from the following diseases: 1.thrombocytopenia, any coagulation disorder, or receiving anticoagulant therapy, etc.; 2.history of congenital or acquired immunodeficiency or autoimmune disease; asplenia, or history of spleen surgery, trauma, or treatment with immunomodulatory agents within 6 months, such as: immunosuppressive doses of glucocorticoids (dose reference: equivalent or prednisone 20mg/day for more than one week); or monoclonal antibody; or thymosin; or interferon, etc.; 3.those suffering from acute infectious diseases or using antipyretic/analgesic/antiallergic drugs within 3 days before enrollment, or acute exacerbation of chronic diseases; 4.cancer patients (except basal cell carcinoma) who have been off treatment for less than 6 months; 5.serious chronic diseases such as congenital heart disease, severe liver and kidney disease, severe diabetes (with complications) that may interfere with the conduct or completion of the study; 6.active tuberculosis, viral hepatitis patients with obvious liver damage (excluding virus carriers) and/or hiv-positive or syphilis-specific antibody-positive; previous history of severe hypersensitivity to any vaccine, or severe hypersensitivity history to any component of the investigational vaccine, including aluminum preparations, such as: anaphylactic shock, allergic laryngeal edema, anaphylactoid purpura, thrombocytopenic purpura, dyspnea, vascular nerve edema, etc.; administer subunit vaccine and inactivated vaccine within 14 days before the trial vaccine, and receive live attenuated vaccine within 28 days; received blood or blood-related products, including immune globulin, within 3 months prior to screening; or planned use within 6 months after study initiation to full vaccination; in addition to completing 2 doses of inactivated novel coronavirus vaccine within the past 3-9 months, participating in other covid-19 related clinical trials; pregnant women (including women of childbearing age with positive urine pregnancy test); investigators believe that the presence of any disease or condition in the subject may put the subject at unacceptable risk; the subject cannot meet protocol requirements; interfere with the assessment of vaccine response, etc.

suspected or confirmed fever (fever ≥38.5℃) within 72 hours before enrollment, or axillary body temperature ≥37.3℃ on the day of enrollment; diastolic blood pressure ≥ 100 mmhg and/or systolic blood pressure ≥ 160 mmhg without or after drug control; have a history of previous infection with new coronary pneumonia or a positive nucleic acid test history; those who currently suffer from the following diseases: 1.thrombocytopenia, any coagulation disorder, or receiving anticoagulant therapy, etc.; 2.history of congenital or acquired immunodeficiency or autoimmune disease; asplenia, or history of spleen surgery, trauma, or treatment with immunomodulatory agents within 6 months, such as: immunosuppressive doses of glucocorticoids (dose reference: equivalent or prednisone 20mg/day for more than one week); or monoclonal antibody; or thymosin; or interferon, etc.; 3.those suffering from acute infectious diseases or using antipyretic/analgesic/antiallergic drugs within 3 days before enrollment, or acute exacerbation of chronic diseases; 4.cancer patients (except basal cell carcinoma) who have been off treatment for less than 6 months; 5.serious chronic diseases such as congenital heart disease, severe liver and kidney disease, severe diabetes (with complications) that may interfere with the conduct or completion of the study; 6.active tuberculosis, viral hepatitis patients with obvious liver damage (excluding virus carriers) and/or hiv-positive or syphilis-specific antibody-positive; previous history of severe hypersensitivity to any vaccine, or severe hypersensitivity history to any component of the investigational vaccine, including aluminum preparations, such as: anaphylactic shock, allergic laryngeal edema, anaphylactoid purpura, thrombocytopenic purpura, dyspnea, vascular nerve edema, etc.; administer subunit vaccine and inactivated vaccine within 14 days before the trial vaccine, and receive live attenuated vaccine within 28 days; received blood or blood-related products, including immune globulin, within 3 months prior to screening; or planned use within 6 months after study initiation to full vaccination; in addition to completing 2 doses of inactivated novel coronavirus vaccine within the past 3-9 months, participating in other covid-19 related clinical trials; pregnant women (including women of childbearing age with positive urine pregnancy test); investigators believe that the presence of any disease or condition in the subject may put the subject at unacceptable risk; the subject cannot meet protocol requirements; interfere with the assessment of vaccine response, etc.