This cross-sectional study assessed the impact of thyroid dysfunction on hematological parameters among 210 individuals. Hyperthyroid patients showed decreased RBC, Hb, and platelet counts, while hypothyroid patients exhibited increased MCV, MCH, and platelets. WBC counts and immune cell profiles also differed between groups. T3 and T4 levels correlated with these hematological alterations. The results indicate that thyroid dysfunction significantly affects blood parameters, aiding early detection and management of related hematological issues.