Pearl oyster seed productivity at present is still low and far from the need for farming activity of pearl oyster. The aim of this experiment was to know the effect of water exchange frequency on growth and survival rate of pearl oyster larva. Completely Randomized Design was used with four treatments and triplicate; i.e. treatment A: 100% water exchange everyday; treatment B: 100% water exchange every 2 days; treatment C: 100% water exchange every 4 days and treatment D: 100% water exchange every 8 days. Treatment B (100% water exchange every 2 days) was considered as the control treatment. The results showed that the growth of pearl oyster larva was affected by water exchange. The optimum treatment was achieved with 100% water exchange every 4 and 8 days (treatment C and D) and the growth was higher than that with treatment A and B. The highest pearl oyster shell length was achieved at treatment D (100% water exchange every 8 days) that was 2082.67
