Cypermethrin (CYP) a type of insecticides is in common use. It has been found to be accumulated in the different body tissues leading to organ dysfunction. This study aimed to investigate the toxicity of CYP on thyroid gland structure and the possible ameliorating effect of ginger. Fifty adult male albino rats were used and equally divided into 5 groups (10 rats/group). Group I received only balanced diet and tap water. Group II rats were given corn oil (solvent of CYP). Group III (ginger extract group) received 750 mg/Kg body weight (BW) by gavage. Group IV (CYPtreated group) rats were given CYP (20 mg/kg BW) dissolved in corn oil by gavage. Group V (CYP and ginger extract- treated group) received CYP followed with ginger extract by the same manner mentioned above. After 14 days, venous blood samples were collected for assaying serum T3, T4 and TSH levels. Rats were anaesthetized then sacrificed. The thyroid gland was harvest for light and electron microscope examinations. The CYP-treated group showed histopathological and ultrastructure changes of thyroid follicles that appeared distended with flattened lining epithelium. Follicular cells showed vacuolation in their cytoplasm. Other follicles were lined by multiple layers of follicular cells (stratification). Many electron empty zones devoid of organelles and disrupted dilated cisternae of rough endoplasmic reticulum were noticed. Absence of microvilli congested dilated blood vessels and many collagen fibers were also detected. Follicular cells had apoptotic nuclei. Such alterations were associated with a highly significant increase in TSH (p<0.001) concomitant with decrease of T3 and T4. On the other hand, coadministration of ginger extract was noticed to ameliorate the damaging effects of CYP on thyroid tissues in animals of group V. It is suggested that co-administration of ginger could alleviate or minimize the possible toxicity resulting from CYP exposure