Objective We study the potential diagnostic use of urinary cytokeretin 19 fragment (CK19,Cyfra21-1). Methods Urinary CK19 was investigated by using an electrochemiluminescence immunoassay(ECLIA) in urin of 47 healthy subjects and 154 patients including 45 with bladder cancer,94 with urological benign diseases and 15 nonbladder cancers. Result The urinary CK19 average level of patients suffered from bladder cancer is (122。00?12。60) ?g/L that is significantly different from the level of healthy control[(1。97?0。88) ?g/L, P