Effects of gamma irradiation on microbiological changes of Gorosoe sap were characterized during a post-irradiation storage at $4^{circ}C$. The aseptically collected sap was irradiated and stored at $4^{circ}C$ for 0 to 60 days and analysed for standard plate counts and 16S rDNA. There were significant differences in the total number of colony forming units(CFUs) of bacteria between irradiated and non-irradiated control sap. Bacteria of non-irradiated sap were present at levels of $1.5{ imes}10^4{sim}2.3{ imes}10^8;CFU/m{ell}$, whereas no viable microbial cells were detected in sap after 10 kGy of irradiation during storage. According to the 16S rDNA sequence analysis, bacterial community structures decrease with time and the most abundant strain was Pseudomonas species. Our results suggested that gamma irradiation can be used to enhance the shelf-life of Gorosoe sap.