📓 The current study evaluates the role of the dietary Vitamin C on the growth, feed utilization and reproductive performance of koi's (A. testudineus). The overall objective of this study was to improve the feed quality and their effects on the seed quality in climbing perch brood stock management in Bangladesh. A significantly positive effect of the highest dietary ascorbic acid level on the brood fish growth and feed efficiency was demonstrated. However, vitamin C did not affect the survival rate. There was no significant effect of vitamin C on Spawning efficiency, ovulation response, egg diameter and fertilization. The higher levels of vitamin C significantly increase egg hatchability similar to fish fed diet with lower levels (600mg/ kg) of vitamin C. The enhancement of growth, feed efficiency and egg hatchability through supplementation of vitamin C in the diet would enable more efficient seed production and aquaculture operations. Therefore off station study is required before dissemination the results of the current study to the end users of fish seed the fish farmers and hatchery owners and managers in home and overseas.