DA-5018, a non-narcotic analgesic agent, was examined for mutagenicity in the reverse mutation test on bacteria, chromosomal aberration test on cultured mammalian cells and micronucleus test on mice. The reverse mutation test was performed by a plate incorporation method with or without a metabolic activation system(S9 mix) using Salmonella typhimurium strain TA100, TA1535, TA98 and TA1537. DA-5018 did not significantly increase revertant colonies in any of the test strains under any conditions at concentrations ranging from 0.0049 to 1.25 mg/plate, compared with the vehicle control. In the chromosomal aberration test using cultured Chinese Hamster Lung(CHL) cells, DA-5018 did not increase the number of aberrant cells in the presence or absence of S9 mix at concentrations of 0.016 mM/plate to 0.25 mM/plate, compared with the vehicle control. In the micronucleus test, male ICR mice were given DA-5018 intraperitoneally at a dose level of 0.55, 1.10 and 2.20 mg/kg. The incidence of bone marrow micronucleated polychromatic erythrocytes in the DA-5018 treated mice was not significantly different from that of the vehicle control. These results indicate that DA-5018 does not have mutagenic potential under the present test conditions.