Objective: To investigate the expressions of TGF-β1 and Smad7 and change of dendritic cells (DCs) in colorectal cancer liver metastases (CRLM) tissue and the clinical significance. Methods: The expressions of TGF-β1, Smad7, CD1α (marker of immature DCs) and CD83 (marker of mature DCs) in resection specimens of CRLM tissue and normal liver tissue around the CRLM with negative margin were determined by immunohistochemical staining. The mutual relations among these expressions in CRLM tissue and their relations with the characteristics of the primary tumor were analyzed. Results: The expressions of TGF-β1, Smad7, and CD1α in CRLM tissue were significantly higher than those in normal liver tissue (all P<0.05), and their expressions showed mutual positive correlations in CRLM tissue (r=0.455, r=0.623, r=0.448, all P<0.05); CD83 expression was negative in almost all the studied CRLM tissue specimens, and only two cases of weak positive expression were found in the normal liver tissue specimens. All expressions of TGF-β1, Smad7 and CD1α were significantly related to the depth of invasion of the primary tumor and lymph node metastasis (all P<0.05), but irrelevant to differentiation of the primary tumor (P>0.05) in CRLM patients. Conclusion: The high TGF-β1 and Smad7 expressions and increased immature DCs number may together promote the occurrence and development of CRLM.