The effects of repeated administration of scopoletin on fructose and citric acid levels of male reproductive organs of guinea pigs were studied. The animals were divided into experimental and control groups. The experimental group was treated with scopoletin 39.50 μg/kg body weight while the control group received 10% dimethyl sulphoxide, the solvent for scopoletin. This level of scopoletin is analogous to the amount taken in cassava consuming populations. The results show that the weight gain (70.9 +/- 2.6g) in the control group was significantly higher than that in the scopoletin treated group (24.8 +/- 3.2g). The mean fructose level of the control guinea pigs were 1.25 and 82.50μg/ml for the testes, and prostate and seminal vesicles respectively while the value for the scopoletin treated group were 0.36 and 2.09μg/ml respectively. Also the mean citric acid levels were 14.30 and 14.47μg/ml respectively for the testes, and seminal vesicles of the scopoletin treated group while they were 0.46 and 2.90μg/ml for the control group. These results represent a significant decrease (P < 0.05 - P < 0.01) in both the citric acid and fructose levels of the male reproductive organs of the control guinea pigs relative to the scopoletin treated group. Because fructose is the energy source of spermatozoa and citric acid is responsible for maintaining the pH of the semen, scopoletin may induce testicular failure at the level of sperm maintenance.