This study was conducted to evaluate the effects of Chaetoceros algae and other supplements (glucose, active char coal and Oxygen balls) on the survival rate during transportation and after 20 stocking days of otter clam Lutraria rhynchaena. Juvenile clams were packed in plastic bags (2 L of seawater 30‰) with the density of 300 ind./bag and preserved during 24 hours at stable temperature of 25^oC. Results showed that total ammonium concentration increased abruptly after 24 hours in the treatments without supplements. Adding glucose and Oxygen balls resulted in higher algal clearance rate of otter clams (70.4 – 75.0%), these levels were significantly higher than those from others (pChaetoceros algae together either glucose, active char coal or Oxygen balls during long transportation to improve the survival rate of otter clam juveniles.