The digestibilities of animal and plant protein sources were determined for P. monodon (30 ~ 40 g wet weight). Protein sources were incorporated in complete diets containing the indicator, chromic oxide at 1.8%. Casein, (APDC=97.9%) was highly digested. The APDC values of shrimp meal (Acetes sp.) and squid meal were 95.4% and 96.0%, respectively. These values did not differ from those for plant protein sources such as soybean meal (93.4%), yeast (93.0%) and wheat germ meal (91.9%). Fish meal (60.75%), meat and bone meal (73.8%) and copra meal (75.2%) had significantly lower APDC values while shrimp head meal and testis meal were digested at 89%~90%. Assimilation (U¹) of dietary organic matter by the ash-free method ranged from 58.3%~90.19%. The TPDC of feedstuffs were generally higher by about 5% than the APDC. A highly positive correlation was observed between APDC and ADMDC (r=90). Protein content of all diets which ranged from 12.9%~60.18% showed no correlation with APDC, TPDC, ADMDC and U¹. This study showed that the shrimp has the capability to similarly digest plant and animal protein sources.