To study the expression of C3aR and C5aR in trichloroethylene-sensitized mouse liver injury and discuss the pathogenesis of Dermatitis Medicamentosa-like of TCE (DMLT).6∼8 w female BALB/c mouse were randomly divided into blank control group, solvent control group and TCE treatment group. TCE was given to the mouse for sensitization at 1th, 4th, 7th, 10th day and challenge at 17th day and 19th day. Before killing mouse, liver weight and body weight were recorded. The livers were separated at 24 h, 48 h, 72 h and 7 d after challenge. And the liver sections were used for immunofluorescence stain and RT-PCR to detect the expression levels of C3aR and C5aR.Microscopic examination showed no significant change in liver structure or organization in TCE non-sensitized group, while liver cell oedema, cell necrosis and inflammatory cell infiltration were clearly observed in TCE-sensitized groups. The expression levels of C3aR and C5aR in 24 h, 48 h, 72 h and 7 d TCE-sensitized groups were significant higher than blank control group, solvent control group and related TCE non-sensitized groups (P < 0.05).Complement activation was involved in TCE-induced liver injury and C3aR and C5aR might play essential role in the process.