For prevention against SARS-CoV-2, various vaccines have been approved globally including Pfizer, Sinopharam, Moderna, Johnson & Johnson etc which have proved quite effective. To evaluate the immunization and safety of Sinopharm vaccine in cancer patients. A prospective study was conducted in the Oncology Department of Nishtar Medical Hospital, Multan from March 2021- September 2021. A total of 150 cancer patients undergoing treatment were included in the study. All the patients were administered 0.5 ml Sinopharm vaccine with 28 day difference between the two doses. A two-month follow-up was done to test the immunization using ELISA kits. Among all the patients, 16 patients (10.7%) had a history of COVID-19 before the administration of the vaccine. At the time of vaccination, 23.3% of patients were seropositive. After the vaccination, 130 patients (86.7%) developed immunity against the infection. 30.6% of participants developed a fever and 20.9% had fatigue. Other side effects were also observed including pain, redness, swelling, itching, chills, anorexia, nausea, vomiting, myalgia and diarrhea. Sinopharm vaccine is effective and safe for patients with malignancies especially in patients receiving radiaton therapy but still recommended for older patients and patients receiving chemotherapy.