Ethnopharmacological relevance Gumiganghwal-tang (GGT, known as Kumi-Kyokatsu-to in Japanese) is a traditional herbal prescription made from nine different herbs that is used for the treatment of the common cold, pain, and inflammatory diseases. Aim of the study This study evaluated the potential genotoxicity of an aqueous GGT extract using three standard battery of tests as part of a safety evaluation. Materials and methods We prepared GGT using a water extraction method and subsequently extracted six compounds from GGT by high performance liquid chromatography. GGT extract genotoxicity was assayed using three standard tests including the in vitro bacterial reverse mutation test, the in vitro chromosomal aberration test with Chinese hamster lung cells, and the in vivo micronucleus test using ICR mouse bone marrow recommended by the Korean Food and Drug Administration. Results The bacterial reverse mutation assay showed that GGT extract doses ranging from 333.3 up to 5000mg/plate induced a greater than 2-fold increase in the number of revertant TA1537 strain colonies exhibiting metabolic activation (with S-9 mix), when compared with the vehicle control. The chromosomal aberration test showed that GGT extract induced an increase in the number of chromosomal aberrations after treatment for 6h with the S-9 mix and 22h without the S-9 mix, when compared with vehicle control. In contrast, the micronucleus test showed that GGT extract did not significantly increase the number of micronucleated polychromatic erythrocytes (MNPCEs) in ICR mouse bone marrow. Conclusions Based on these results, it was concluded that GGT extract acted as a genotoxic material in our experimental conditions. We did not identify the compounds responsible for the induction of genotoxic effects, but it was significant that we provided a basic genotoxicity profile for GGT.