Introduction: This study investigated short- and long-term effects of khat (Catha edulis) on hypophyseal, epididymal and testicular morphology, body weight and temperature changes and haematological parameters of rabbits. Materials and Methods: Twenty five male New Zealand White rabbits, divided into five groups were used. First four groups were administered, via intra-gastric tube, 1.5, 4.5, 13.5 and 40.5 g/kg body weight respectively of khat extract thrice a week for 8 weeks while controls received normal saline. Short-term and long-term effects were evaluated for hypophyseal, epididymal and testicular morphology, body temperature as well as body weight changes, food consumption and haematological parameters. Data on haematological parameters, body weight changes, body temperature and food consumption was done using one-way ANOVA at 95% confidence interval using SPSS version 12.0. Results: There was vacuolation in spermatogonia and spermatocytes at high doses while epididymides and hypophyses were unaffected. A significant decrease (P<0.05) in body weight of treatment groups correlated with reduced food intake with increasing doses and chronicity of exposure. Packed cell volume, red blood cell count and haemoglobin concentration decreased while white blood cell count increased with increasing doses. Conclusion: Khat extract had direct effects on spermatogenesis compounded by poor body weight gain, hyperthermia and blood volume loss.