Several studies have demonstrated that herbal plants contain various potential antioxidants and these antioxidant components may be potential antimutagens or anticarcinogens. Glechoma hederacea belongs to the Labiatae family. According to ancient Chinese prescriptions, G. hederacea was used for treating diuresis and stimulating blood circulation. However, there are few reports on its biophysical functions to date. The objective of this study was to evaluate the antioxidant, mutagenic and antimutagenic activities of the hot water extract of G. hederacea (HWG). G. hederacea was extracted with distilled water at 100℃ for 3h. The antioxidant activities tested included α,α-diphenyl-ß-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) and superoxide anion radical-scavenging effects, Fe^2+ -che1ating ability, reducing power and lipid peroxidation inhibition. The in vitro mutagenic and antimutagenic properties of the extracts were investigated using the Ames test. The results showed that HWG possessed antioxidant characteristics. Moreover, the antioxidant activities of HWG were significantly higher than those of Vitamin C and Trolox in terms of superoxide anion radical scavenging activity and Fe^2+ -chelating ability (p < 0.05). The results of Ames test indicated that HWG had no mutagenicity toward all tester strains including Salmonella typhimurium TA97, TA98, TA100, TA102 and TA1535 with/without the metabolic activator (S9 mix). The extracts had marked inhibition effects against the mutagenicities of the diagnostic mutagens with the S9 mix System. The HWG showed antioxidant and anti-mutagenic potential. However, the active compounds of HWG need be further investigated.