Piper guineense is used as spice and herb, particularly to enhance libido. P. guineense has effects on penile erection and copulatory behaviour which are controlled by androgens. This study was carried out to evaluate the effects of consumption of P. guineense leaves on testicular histoarchitecture. The effects of P. guineense ingestion, in form of pelleted formulation, on the histoarchitecture of the testis of adult male Wistar rats were studied. Thirty adult male Wistar rats were divided into six groups labelled A-F. Group A animals served as the control and they were fed ad libitum throughout the experiment. Dried and powdered P. guineense leaf was added to the feed of the rats in Groups B, C, D, E and F in graded proportions. Based on the well monitored and properly evaluated rate of feed consumption, the proportion of P. guineense in the feed for Groups B, C, D, E and F gave approximate daily dosage of 100, 200, 300, 400 and 500 mg/kg body weight respectively. The regimen design was to observe the possible influence of dosage variations.