The present study assessed in vivo endocrine disrupting effect of orally administered lambda-cyhalothrin (LCT) on metabolic hormones and correlated it with hematological instabilities. Adult female albino rats were divided in three equal groups; one kept as control and other two treated with 20 and 40 mg/kg BW LCT, respectively by oral gavage for 14 days. At the end of trial, blood was collected for hormonal and hematological analysis. The results showed that LCT led to reduction in serum triiodothyronine (T3) and thyroxin (T4) level (P<0.001) without modifying serum thyroid stimulating hormone (TSH) level in a dose related manner. Lambda-cyhalothrin also caused a significant (P<0.05) reduction in hemoglobin (Hb) concentration, red blood cell (RBC) count, total leukocyte count (TLC), platelets count, pack cell volume (PCV) and lymphocyte count. No significant variation was observed in erythrocytic indices. In sum, orally administered LCT caused reduction in feed intake and body weight along with disruption of hemato-biochemical parameters