Abstractγ‐Glutamyl transpeptidase (GGT) was extracted from squamous cell carcinoma tissues of human skin (SCC) by Triton X‐100 and bromelain treatment, and some of its biochemical properties were compared with those of GGT extracted from eccrine gland‐rich tissue and normal kidney. GGT activity significantly increased in SCC, but there was no definitive differences in enzymological properties between GGT of SCC and normal tissue enzyme. However, GGT of SCC was distinguishable from those of normal tissues by isoelectric point, electrophoretic mobility, and sensitivity to neuraminidase treatment. These results indicate that GGT of SCC has some variant properties which may be related to skin carcinog