Triethyleneglycol-dimethacrylate (TEGDMA) is a monomer and widely used in dental composite resins. TEGDMA has been found to exhibit cytotoxicity and genotoxicity on many cells. However, little is known about the potential toxicological implications of TEGDMA on murine macrophage cell line RAW264.7. In this study, TEGDMA demonstrated a cytotoxic effect to RAW264.7 cells in a concentration- and time-dependent manner (p < 0.05). TEGDMA was found to induce two modes of cell death in a concentration-dependent manner (p < 0.05). TEGDMA-induced cell apoptosis was demonstrated by the increase in the portion of sub-G0/G1 phase and DNA ladder formation. In addition, TEGDMA exhibited genotoxicity via a dose-related increase in the numbers of micronucleus and DNA strand breaks (p < 0.05). Furthermore, the activation of caspase-3, −8, and −9 were generated by TEGDMA in a dose-dependent manner (p < 0.05). These results indicated that cytotoxicity and genotoxicity induced by TEGDMA in macrophages may be via DNA damage and caspase activation. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 581–588, 2015.