Animal protein sources in fish feeds are expected to be greatly decreased as a consequence of increasing economic, environmental and safety issues. Research for fish nutrition has recently focused on the development of practical diets with minimal levels of fish meal and alternative lower-cost protein sources. At the present study, primarily, rice bran protein concentrate (RBPC) was produced with alkalinity method and, then, were used in rainbow trout diets at three levels (10, 25 and 35%) as a fish meal replacement. One diet was taken as control without replacing. Alvine fed these diets for 30 days after the start of feeding. The survival was significantly (P<0.05) higher in control but there was no significant difference among others (P>0.05). High final weight and weight gain and SGR were observed at the end of trial for RBPC-10 diet (P<0.05). The highest and lowest of PER and LER was observed in control and RBPC-35 groups, respectively. But these factors had no significant difference between RBPC-25 and RBPC-10 (P>0.05). Based on a proximate analysis, the groups fed RBPC-35 showed lower protein and higher lipid in body composition (P<0.05). Results of amino acid profile of fishes fed plant protein showed that the amount of Glysine increased at 25 and 35% of RBPC. Also, histidine decreased at all diets compared to the control. The lowest amount of lysine was found at RBPC-35. In conclusion, fish meal can be substituted with up to 25% RBPC in larval stage of rainbow trout without any growth reduction.