Background: Individuals with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) face a heightened risk of severe coronavirus disease 2019 (COVID-19). However, the effectiveness and safety of vaccines relative to the broader population has been a subject of debate. Objective: To assess immunogenicity and to compare adverse effects following COVID-19 vaccinations in patients with SLE and RA vs matched healthy controls. Patients and methods: This work included 30 SLE, 30 RA and 30 age and sex-matched healthy controls. Assessment was done 2-6 weeks after BBIBP-CorV (Sinopharm BIBP COVID-19) vaccine including measuring serum IgG neutralizing anti-spike antibodies, a questionnaire for adverse events and assessing disease activity for patients. Results: There wasn't significant difference in the titer of neutralizing antibodies between patients and controls (p= 0.51). Fatigue, local redness, and swelling were more in control group (p < 0.0001, p=0.008 and p=0.008 respectively). Tingling sensation was higher in patients (0.006). Disease activity was significantly higher in RA and SLE patients after vaccination (p=0.001 and p=0.002 respectively). Flares occurred in 12 (40%) of SLE patients and 13 (43%) of RA patients, mainly in a mild form (58% of flares in SLE and 62% in RA). Conclusion: The BBIBP-CorV (Sinopharm BIBP) COVID-19 vaccine is immunogenic in patients and control groups. Adverse events were mainly minor with less frequent fatigue, local swelling and redness and more tingling sensation among SLE and RA than controls. In RA and SLE patients, disease flare may occur after COVID-19 vaccine mainly in a mild form.