Background: Worldwide, a coronavirus disease called COVID-19 has affected sizable populations. Although there has been a lot of excitement about vaccines, little is known about their negative effects or how antibody titters change following injections. The objective of the study is to evaluate post-vaccine IgG titters, WBCs count after Pfizer COVID-19 Vaccine and side effects in the Garmian District. Materials and Method: The data were collected from Sherwana primary health center in Kalar, Kurdistan region, Iraq, from September 25th to December 23rd 2021, which included 120 unvaccinated controls and 115 general population participants were enrolled in a COVID-19 vaccination campaign. A questionnaire form was used which included is socio-demography, clinical history, vaccine side effects. All 115 participants underwent two Pfizer COVID-19 vaccines and blood samples were collected 4 weeks after the 1st dose and 6–8 weeks after the 2nd dose of vaccination, and then the laboratory tests for the immunological (IgG) and white blood cells were performed. Result: The level of antibodies increased significantly after the 2nd dose of vaccines compared to the 1st dose. Younger age, non-chronic disease participant, COVID-19 positive, smoking, and AB blood group type, significantly associated with higher IgG titres after Pfizer COVID-19 vaccination. The non-vaccinated severe infected group had significantly higher antibody titters and WBC counts than the mild and moderate infected groups. Individuals with the 1st dose vaccinated have a higher level of side effects compared to vaccinated individuals with the 2nd dose at vaccine. Conclusion: After receiving two doses of the Pfizer COVID-19 vaccine, all research participants developed antibodies. The research population appears to be at no risk from the Pfizer COVID-19 vaccine, and the antibody titer rose following the two rounds of immunization. The participants' aging and the presence of non-chronic conditions are blamed for the rise in antibody titter.