Background: Melodinus cochinchinensis (Lour.) Merr. is a medicinal plant, which is used as a folk medicine for treating meningitis and fractures. However, the anti-inflammatory activity of total alkaloid extract from M. cochinchinensis (MCTA) and its molecular mechanism are still not studied.Purpose: The aim of this study is to investigate the main chemical constituents of MCTA and explore its antiinflammatory potential in both in vitro and in vivo assessments.Methods: UHPLC-ESI-HRMS/MS was applied to analyze the chemical profiling. The anti-inflammatory efficacy of MCTA was evaluated on lipopolysaccharide (LPS) induced RAW 264.7 cells and two common inflammation models in mice. The production of pro-inflammatory mediator and cytokine was tested using the ELISA method. The pathological change was analyzed by histological assessment. The expression of NF-kappa B, MAPKs and PPAR-gamma proteins was evaluated using western blot analysis.Results: A total of 21 monoterpenoid indole alkaloids (MIAs) were characterized by UHPLC-ESI-HRMS/MS. Aspidospermine- and quinolone-type alkaloids were found to be the major compounds. MCTA significantly decreased the production of NO, IL-1 beta, IL-6 and TNF-alpha in LPS-induced RAW 264.7 macrophages. MCTA significantly inhibited the phosphorylation of ERK1/2, JNK and p38 MAPK, suppressed the NF-kappa B transcriptional activation and improved the PPAR-gamma expression. Moreover, the in vivo experiment exhibited that MCTA pretreatment markedly alleviated the xylene-induced ear edema and carrageenan-induced paw edema in mice and decreased the IL-1 beta, IL-6 and TNF-alpha expressions.Conclusion: MCTA is rich in MIAs and exhibited a significant inhibitory effect on the production proinflammatory cytokines. The mechanism might be related to the inhibition of activation of NF-kappa B and MAPK pathways.