Dibroacetic acid (DBA) is a byproduct of drinking water disinfected by halogenation and it belongs to halogenated acetic acids. It also can be found in ozonated drinking water. Four short-term assays were performed to detect the genotoxic activity of DBA. In the Ames test, DBA showed mutagenic activity in Salmonella typhimurium strain TA100 with or without rat liver-derived metabolic activation system (S9). In UDS test, DBA was found to induce DNA damage in rat primary hepatocyte. Mouse bone marrow micronucleus test indicated that DBA induced the damage of chromosome. In NIH3T3cell micronucleus test, DBA increased the number of micronuclei in cells. Our results suggest that DBA induce DNA damage and has genotoxic activity.