Objective: To collect and analyse epidemiologic data of all malignancies by age group and gender for the Karachi population to estimate the cancer incidence of 5-years (2017-2021) and identify major risk factors for setting priorities towards cancer control programs. Study design: Observational study. Place and Duration of the Study: Karachi Cancer Registry (KCR) Secretariat, Pakistan Health Research Council (PHRC), JPMC, Karachi, from 2017-2021. Methodology: Cancer data of seven tertiary care hospitals of Karachi submitted to KCR during the study period were analysed including age, gender, date of first contact, primary site and ICD coding. All the data was cleaned, merged, and analysed. All patients 0-14 years were classified as \u27children\u27, all aged 15-19 years were classified as \u27adolescents\u27, and those age 20-years and above as \u27adults\u27. Age standardised incidence rates (ASIR) were determined for both genders. Results: During the last five years (2017-2021), a total of 65,886 malignant cases were received. The distributions seen amongst males and females were 33,510 (51%) and 32,376 (49%), respectively with 60,145 (91.3%) tumours found in adults (≥20 years), 4844 (7.3%) in children, and 897 (1.4%) in adolescents. The three most common tumour sites were oral, liver, and colorectal in males; breast, oral and ovary in females; bone, brain and connective tissue in adolescents; and leukaemia, brain and bone in children. The overall ASIR (%) in males was 89.20 for adults, 9.19 for children, and 1.61 for adolescents. The overall ASIR (%) in females was 93.44 for adults, 5.45 for children, and 1.11 for adolescents. Conclusion: Oral cancer, a largely preventable cancer is the leading cancer in males while breast cancer is the leading cancer in females followed by oral cancer. In adolescents and children, the incidence closely matches most of the worl