The Effects of Eurycoma longifolia Jack were studied on the sexual behaviour of male rats. Sexually normal male rats were treated twice daily with 500 mg $kg^{-1}$ / of different fractions of E.longifolia Jack for 10 days prior to test and were then observed for their copulatory behaviour with a receptive female in a copulation cage. Results showed that was a significant increase (p<0.05) in EL-1, EL-2, EL-3 but significant decrease (p<0.05) in both PEI-1 and PEI-2 in treated male rats as compared to the control male rats indicating that E. longifolia Jack increased the sexual performance of the treated male rats by extending the duration of coitus and decreasing the refractory period between the different series of copulation. Hence, this preliminary work supports the folk use of this plant as having aphrodisiac property.