Black pepper (Piper nigrum L.) is one of the most widely used spices which has many pharmacological effects and several health benefits. However, it is known to piperine of black pepper provide inconsistent effects on virility and fertility in male. In this study we aim the effect of black pepper fruit extract on testicular function—both hormonal and histological—in alloxan-induced hyperglycaemic rats. A total 24 male Sprague Dawley rats divided into four group (6 rats each). Group 1 (control) consisted of rats provided with food and water *ad libitum*. Group 2 consisted of rats induced with alloxan (150 mg/kg BW) on days 0 and 14 to serve as the hyperglycaemic group. Groups 3 and 4 consisted of hyperglycaemic rats administered black pepper extract every two days for 28 days at doses of 122.5 mg/kg BW and 245 mg/kg BW, respectively. The measured parameters included blood glucose levels, total testosterone levels, sperm quality (count, motility, and abnormalities), and testicular histological parameters (counts of type A spermatogonia, preleptotene spermatocytes, pachytene spermatocytes, spermatids, and Leydig cells). The results showed that hyperglycaemic rats treated with black pepper fruit extract exhibited reduced blood glucose levels, increased total serum testosterone, and improvements in sperm count, motility, and viability, alongside a decrease in sperm abnormalities. Histological analysis of the testes revealed an increase in the number of spermatogonia A, preleptotene spermatocytes, pachytene spermatocytes, and spermatids, as well as an increase in Leydig cells. Based on these data, it can be concluded that black pepper fruit extract has a curative effect on testicular dysfunction in alloxan-induced hyperglycaemic rats.