Abstract:In the present study experimental out bred population of Drosophila nasuta used, has been originated from progenies of 50 isolated female lines collected at Chamundi hill at Mysore, India. It was found that males of D. nasuta discriminated females on the basis of their age and prefers to mate more frequently with younger of the two competing females. Although middle aged females mated faster and copulated longer compared to young and old aged females. Males showed grater courtship activities such as tapping, scissoring, vibration, liking to middle aged female compared to young or old aged females. Middle aged females showed least rejection responses such as ignoring, extruding, and decamping to courting male than young or old aged females. Young aged females laid significantly greater number of eggs and produced more progenies than middle and old aged females. Further young aged females had greater number of ovarioles than those of middle and old aged females. Thus these studies in D. nasuta suggest that female age has significant effect on male mate preference.