This investigation is to study the effect of processing technique of some raw materials on chemical analysis, growth performance and feed utilization of Nile tilapia fingerlings. This experiment was carried out at the Fish Research Center, Faculty of Agriculture Suez Canal University. Three plant protein sources were used (Linseed meal (LSM)), groundnut meal (GNM) and soybean meal (SBM)), three processing procedures was used (autoclaving (AC) - soaking (SK) and long term fermentation (L-TF). Four experimental diets were formulated to contain approximately 30% crude protein. At the end of experimental period growth performance, feed utilization and economical evaluation were statistically analyzed. The results revealed that processing effect on chemical analysis of all feed ingredients. In Linseed meal Autoclaving have major effect on nutritional composition than the rest of other raw materials were tested. Crude protein content increased in autoclaving (47%), soaking (43% and long term fermentation (49%). Crude lipid content increased from 20.5 to 22.1, 25.1 and 25.4% in AC, SK and L-TF respectively. Crude ash contents were reduced by all treatment processes except autoclaving process. In GNM, the results showed that Autoclaving approximately increase9% in crude protein, crude lipid significantly (P<0.05) increased by Sk and L-TF .While AC had no significantly effect on crude lipid content. While crude Ash content increased by AC, SK and L-TF. In soybean meal autoclaving had no significant difference in dry matter percent. While SK and L-TF significantly increased difference (P<0.05) in SK and L-TF. Crude protein content increased from 44.0 in UP to 48.0 and 52.0%in SK and L-TF. Crude lipid content increased significantly (P<0.01) from 18.5 to 21.8 and 20.6% in SK and L-TF. Moreover crude ash content decreased significantly (P<0.01) from 5 to 4.3 and 4.2% in SK and L-TF. After processing in SBM dry matter significantly (P<0.05) increased in SK and L-TF .While crude protein content significantly (P<0.01) increased to 48 and 52 in SK and L-TF. Crude ash content decreased significantly (P<0.01) to 44.30 and 4.20% in SK and L-TF. Results of growth performance parameters showed that final body weight (FBW), weight gain (WG) and specific growth rate (SGR %) of Nile tilapia Oreochromis niloticus fingerlings were significantly recorded the highest values on autoclaving and fermentation techniques while soaking and Unprocessed had the lowest final body weight, weight gain, weight percent and SGR. The highest values of FBW (39.24g), WG (18.80g) and SGR % (0.39%) were recorded in fish fed autoclave diet. Data indicated that Food Conversion Ratio (FCR) were significantly (P < 0.05) different and the best values were recorded in Autoclaving and fermented diets (1.80 and 1.80).