The present study was undertaken to determine whether starvation could affect the exocrine pancreatic function in the rats. Male Wistar-Imamichi rats of 9 weeks of age were starved and changes in concentration of pancreatic enzymes during starvation period were examined. Amylase concentration started to drop from day 3 of starvation and decreased progressively to a level of 20% of that in the control rats on day 12. The concentrations of protease and trypsin, however, remained relatively unchanged by day 3 or 6, from that time, started te increase. Protease concentration reached a value, three and half times higher than that of the control rats on day 12. Plasma glucose concentration showed a slight decrease in the starved rats as compared to the control rats during starvation period. Plasma insulin level, in contrast, in the rats starved for 3 days was about one-tenth of that in the control rats. A treatment of insulin prevented a decrease in amylase concentration in the starved rats. Similar changes in pan reatic enzyme concentrations, decrease in amylase and increase in protease, were observed in the alloxan diabetic rats and the decrease in amylase concentration was recovered by insulin treatment. Based on these findings, it is concluded that the change in amylase concentration during the starvation period may be a result of a decrease in plasma insulin concentration.