Abstract: The current study was done during the period from December 2013 to January 2015 to detect the mutations of GSTM1 and GSTT1 in bladder cancer patients. A total sixty fresh tumor biopsies from patients of Transitional cell carcinoma (TCC) and thirty fresh biopsies of cystitis as control used in this study. GSTM1 mutation of patient group was significantly higher (P<0.001) than that of control group while GSTT1 mutation was not significant in bladder cancer patients. There are a significant correlation between GSTM1 mutation with smoking (P=0.047) and advanced tumor stage (P=0.006) and also between GSTT1 mutation with smoking (P=0.002) and higher mean age (P = 0.025