Vernonia amygdalina (bitter-leaf) is native to West Africa but occurs mostly in its cultivated form in various parts of central and southern Nigeria. It is a dark-green leafy vegetable commonly used in cooking and as folkloric medicine for the management of several diseases in Nigeria. In the present study, the effects of varying doses of ethanolic leaf extract of Vernonia amygdalina on the rat testis histo-morphometry were investigated. Forty male wistar rats were divided into groups of four. Group A, as the control was given 10 ml/kg/day/oral distilled water while Group B, C and D subsequently treated with 100, 300 and 600 mg/kg/day/oral route Vernonia amygdalina leaves extract respectively for 56 days. Results showed that Group B rats had normal testis histology comparable to the control group. However, rats in Group C and D exhibited dose-dependent poor testes histo-morphometric profiles, with the higher dosage-group (D) providing a worse feature. Thus, there was a statistically significant (p < 0.05) reduction in the tubular diameter, cross-sectional area of the tubules, number of tubular profiles per unit area and the mean numerical density of seminiferous tubules of Group C and Group D animals compared to the control group. Our results therefore indicated that, while the lower dose (100 mg/kg) of Vernonia amygdalina leaves extract can be accommodated by rat testis, the higher doses (300 mg/kg and 600 mg/kg) demonstrate testicular toxicity in the rat.