In the present study the effect of electron beam irradiation on the quality of tilapia fish chunk were studied. Tilapia fish chunks were vacuum packed and exposed to 2.0 kGy and 4.0kGy doses of electron beam irradiation and kept under chilled storage. Biochemical parameter includes proximate composition, pH, total volatile base nitrogen (TVB-N), peroxide value (PV) and thiobarbituric acid (TBA) were analyzed. pH values showed an increased trend (6.85 to 7.10) during storage. Fresh tilapia fish chunks had total volatile base nitrogen (TVB-N), peroxide value, thiobarbituric acid (TBA) value of 2.8 meq.O2/kg, 0.05mgMDA/kg,1.05% of oleic acid, 10.2 mg% of TVB-N, respectively. Results showed increased trend in TVB-N, PV, TBA values during storage. Control reached TVB-N value of 30.8mg% on 16th day. However, 2.0kGy, 4.0kGy irradiated sample reached the maximum acceptability level on 30th day (32.50 mg%),41st day (35.8mg%). Total plate count was lower in irradiated sample than control. Similar trend also observed for pseudomonas and H2S former count. There is a significant (p<0.05) reduction in Brochothrix thermosphacta and lactobacillus count in the irradiated sample. Based on the microbial and sensory analysis control had a shelf life up to 16thday. However, electron beam irradiated sample had extended shelf life of 33-41days with respect to dose level.