Forty New Zealand White (NZW) rabbit males aged 12 weeks and weighing 1540.80±22.16 g were equally and randomly divided into four groups (10 in each). All groups were fed a commercial pelleted diet and the first group was served as a control, while diet of the second group was supplemented with 5 g pumpkin seed oil/kg diet (PSO), the third group received 5 g black seed oil/kg diet (BSO), however the fourth group received 5 g from both PSO and BSO/kg diet (PSO+BSO). Results showed that male rabbits in PSO+BSO group showed the heaviest (P<0.05) live body weight (LBW), total weight gain (TWG), average daily gain (ADG), feed conversion ratio and performance index, followed by those in PSO or BSO groups, while males in control group had the light values. Male rabbits received diet supplemented with PSO+BSO combination reached puberty significantly (P<0.05) faster compared with control group, while PSO or BSO groups were intermediate with insignificant differences. Moreover, buck rabbits in PSO+BSO group showed the highest (P<0.05) scrotal circumference, testicular index, weights of testes, epididymis and sexual accessory glands (included seminal vesicles, prostate and the paired bulbourethral (Cowper's gland), plasma testosterone concentration at puberty and the short reaction time and latency period, followed by those in either PSO or BSO groups, however bucks in control group had the lowest values. Semen volume and gel, pH value and semen color score were significantly (P<0.05) higher in PSO+BSO group than that in control group, PSO or BSO groups had intermediate values with insignificant differences. Semen color tended to be milky in PSO+BSO and BSO groups and heavy watery in PSO and control groups. All semen characteristics differ significantly (P<0.05) among the different collection weeks with a tendency to improve with advancing age. The PSO+BSO group showed highly (P<0.001) significant of percentages of sperm motility, livability, sperm cell concentration and the lowest sperm abnormality percentage, followed by PSO or BSO groups, however the control group had the lowest values. All sperm characteristics were significantly (P<0.05) differ among the different collection weeks and improved with age progress. Bucks in PSO+BSO group recorded the highly (P<0.001) significant of total count, total motile, total live and total normal per ejaculate, followed by those in PSO or BSO groups, however, the lowest in control group. Also, all counts of spermatozoa were significantly (P<0.05) differ among the different collection weeks and tended to increase with age.