Current study work was carried out to estimate the influence of phytase addition on mineral availability to fishfingerlings fed Moringa oleifera leaf meal (MOLM) based test diets. Anti-utritional factors (phytate) are present in plant by-products reduces the bioavailability of minerals to fish, resulting in poor fish erformance. Test ingredient was used as M.oleiferaleaf meal (MOLM) to prepare six experimental diets that were supplemented with graded levels of phytase (0, 300, 600, 900, 1200 and 1500 FTU kg-1). The fingerlings were fed at the rate of 4% of live wet weight twice a day and feces were collected from each tank. On the basis of results it was noted that addition of phytase showed clearly significant (p<0.05) enhancement in bioavailability of minerals. Maximum ADC% of minerals was noted at 900 FTU kg-1 level of phytase supplemented MOLM based test diet. By these results, we conclude that addition of phytase at 900 FTU kg-1 level is helpful to develop an eco-friendly and cost-effective fish feed by using MOLM based diet.