Objective To investigate the effects of ethanol extracts of Lepidium meyenii Walp (LMEE) from two different areas in Xinjiang on the maturation of mouse macrophages (RAW264. 7 cells) and dendritic cells (DCs). Methods Ethanol extracts of LMEE from Tashikuergan County (Ta xian) and A La gou of Xinjiang were prepared and named as LMEE-T and LMEE-A, respectively. RAW264. 7 cells and bone marrow-derived DCs from C57BL/6 mice were treated with different concentrations of LMEE-T/A. The viability of RAW264. 7 cells was analyzed by MTT assay. Expression of costimulatory molecules and MHCⅠ on the surface of RAW264. 7 cells and DCs was detected by flow cytometry. Secretion of cytokines and the release of nitrogen oxide (NO) were measured by ELISA and Griess method, respectively. Results LMEE-T/A had no significant influence on the viability of RAW264. 7 cells when the concentration was lower than 1 mg/ml. Treating RAW264. 7 cells with LMEE-T/A promoted surface molecule expression, cytokine secretion and NO release through TLR4 signaling pathway in a dose-dependent manner. Moreover, LMEE-T was more potent than LMEE-A. LMEE-T/A at the concentration of 0. 4 mg/ml promoted the expression of DC surface molecules and the secretion of cytokines. Infrared and ultraviolet spectra showed that LMEE-A and LMEE-T contained polysaccharides, macaenes, macamides and flavanols. Compared with LMEE-A, LMEE-T contained more benzene ring compounds but less polysaccharides. Conclusion Both LMEE-T and LMEE-A could activate RAW264. 7 cells and promote the maturation of DCs. The differences between their effects might be related to the differences in their contents.