Arginine supplementation required for adequate nutrient requirement to stimulateanabolic processes, such as protein synthesis and proliferation.The purpose of this studyis to discover the effect supplementation of arginine on identified protein that functions inpathway of protein synthesis in HepG2 cells.HepG2 cells and arginine were used in thisstudy as the main materials.The main methods that were used are cell culture, iTRAQand western blot.The software packages were utilized for data analysis: Mascot foridentification and quantification of differentially expressed proteins and String to provideinsight into COG function.The result of arginine supplementation via iTRAQ assayshowed that total differentially expressed protein on resupplementation group is higherthan deprivation group and most of protein that detected is up-regulated protein.Ondeprivation group found decreased activity of AMPK on mTOR pathway, AMPK andAtg8 activity in regulation of autophagy pathway.Decreasing AMPK will increasemTOR activity that will inhibit autophagy and induce protein synthesis in HepG2 cells.For GO analysis can be known that the identified proteins represent the relevance andvariety of molecular functions on binding and catalytic activity, acts in cellular andmetabolic process, and large number found located in cell and organelle on all groups.The important protein that find in this study is pyroline-5-carboxylate dehydrogenaseconverts glutamyl-γ-semialdehyde into glutamate.Glutamate is the result of arginineconversion, which has role in protein formation.Validation by Western Blot analysisshown during 8 h arginine deprivation decreases level of p62 and LC3, but increase S6Kand phosphorylation of mTOR by 4 mM arginine resupplementation in HepG2 cells.Inconclusion, arginine resupplementation will increase identified protein, inhibit autophagy,and can used for protein synthesis via increasing mTOR activity in HepG2 cells.