Abstract: Grape pomaces are low-cost natural antioxidant and antimicrobial source and surplus by product of the food processing industry. The aim of this study was to evaluate the effect of adding a red grape pomace by product extract to filleted fish and compare the shelf life of the samples with control. In this experiment, acetone 70% (v/v) was used to extract the phenolic compounds of by Colorimetric Method and concentrations of 0, 2 and 4% extraction were added to samples. Shelf life evaluation was done by determining of the Total Viable Counts (TVC) and Psycrophilic Total Count (PTC). Sensory analysis and Total Volatile Bases-N (TVB-N) were also measured to assessing quality. The sensory acceptability limit was before 6 days for fillet stored in refrigerator and 9 days for fillet prepared from 2% extract and 12 days for fillet with 4% extract. Results showed that amount of pH, TVN, TVC and PTC increased. According to bacterial analysis shelf life in treatments containing 2% extracts 3 days and in treatments with 4% extracts 6 days was larger than control. Overall, 4% concentration made available best preservation condition according to qualitative characteristics (color, odor, texture, taste and flavor). Therefore, it is suggested using preservation of fish fillet.