The present study was conducted to record the seasonal variation in the histomorphology and the histochemistry of the ampulla of vas deferens of Gaddi goat and Gaddi sheep, one of the most important breeds of Himachal Pradesh, India. The study was conducted over a period of year during different seasons viz. spring (March - May), summer (June ­ August), autumn (September- November), winter (December-February).Six adult animals of each species were utilized to study histomorphology and histochemical in each season. Ampulla showed distinct three layers viz. tunica mucosa, tunica muscularis and tunica adventitia. Tubulo-alveolar glandular end-pieces (alveoli, tubules and solid end ­ pieces) were present in the propria-submucosa. The lining epithelium of the tunica mucosa, alveoli and tubules consisted of pseudostratified columnar epithelium. The cojunctive tissue present in between glandular end-pieces consisted of collagen and reticular fibers. The tunica muscularis consisted of two distinct layers (inner circular and outer longitudinal) consisted of mainly smooth muscle fibers, collagen fibers and few reticular fibers in Gaddi goat and sheep. The tunica adventitia consisted of loosely arranged network of collagen, elastic and reticular fibers and occasional autonomic ganglion in Gaddi goat only. The diameter of glandular end-pieces, secretory epithelial height of alveoli and tubules was highest in autumn season and lowest in summer season in both species. Similarly the secretions, apical blebs recorded more in autumn season followed by spring, winter and summer. The secretions and secretory blebs stained intensely for diastase resistant PAS carbohydrates indicating that there may be presence of mucopolysaccharides (other than glycogen as it would have been digested by diastase treatment) that serve the nutrition to ejaculated spermatozoa. The cholesterol was also more in autumn as compared to other seasons in both species. In spring and winter it was more or less same. As the cholesterol is the basic precursor for testosterone.