The objections of this study are to find a proper feeding quantity for the pond management of hard clam to minimize accumulation of organic matter in pond bottom soils, and reduce the impact on pond water and sediment quality. It was designed twice a week for the feeding frequency, Four different feeding quantity were 50 g (A), 100 g (B), 150 g (C), and 200 g (D) for once of each feeding. The effect of feeding quantity on the growth and survival of hard clam, pond water and sediment quality was studied in a 5- month growth trial. There was significant difference in the final weight among the treatments (p < 0.05). Average weight was 7.55, 6.00, 5.43, and 4.74 g for B-, C-, A-, and D-clam, respectively. Survival was behind 84.1-92.7%, group D had the lowest survival than the other groups was significant different (p < 0.05). There was a significant different (p < 0.05) on exchange volume of pond water, too. Exchange volume of group A & B were lower than group C & D. Rearing after 3 months, ammonia-N concentration of group C & D were higher than group A & B. The accumulation of organic matter, ammonia-N and sulfide were increasing gradually in pond soils during early three months. Feeding quantity was more increasing. The amount of sediments was more accumulating in pond bottom soil. Redox potential in the pond soil decreased with the rearing time. The group that had more amount of food was lower redox potential.