In the present study, serum TPA- P2- microglobulin and GST isoenzvnies of 62 cancer pa-lents (24 F. 38M) aged between 17-87 years and 35 (l 1 F. 24 M) healthy controls aged between 21-59 years were investigated. TPA. /32-microglobulin, GST-1-1 and GST-a of cancer patients were 356.3±59.4 UIL, 3.74±1.68 jia lfnl, 28.4±133 righnl and 4.74±3.95 nglml whereas those (.,?f controls were 74.1±34.6 U1L. 2.55E).66 pgiml. 22.1±-10.8 and 4.57±3.2 ng/ml respectively. The differences between TPA, 02-microglobulin and GST-il of the groups were statistically significant. On the other hand, GST -p o f 42 cancer patients (60%) were po-sitive. That percentage is similar to that of healthy people. As a result, simultaneusly determination of the above parameters was concluded to be a sig-nificant criterion in the diagnosis of cancer.