The outcome after resection of hepatic metastases from colorectal cancer is influenced not only by factors of metastatic lesions but also those of primary disease. To clarify whether primary disease factors are predictive of post-resection outcome of colorectal liver metastases, 180 patients (male : female = 114 : 66; 61.1 +/-10.5 yrs; synchronous: metachronous = 95 : 85; colon: rectum = 124 : 56 who underwent surgery of colorectal liver metastases in Cancer Institute Hospital from 1995 to 2005 were recruited for analysis. Post-resection outcome of the patients with colorectal liver metastases was significantly influenced by 1) depth of invasion, 2) grade of lymph node metastasis , 3) number of metastatic lymph nodes and 4) Dukes stage of primary disease. The patients with lymph node metastases further than grade 3 showed median survival time of less than 2 years and did not survive longer than 5 years. Thus such condition seemed not warrant resective treatment for liver metastases. In case of synchronous metastatic disease, primary disease information, such as lymph node metastases, depth of invasion, and Dukes stage, were significant predictive factors after hepatectomy. Meanwhile, such factors did not show significant influence in the patients with metachronous liver metastases. In conclusion, influence of primary disease factors should be considered for deciding the indication of hepatectomy for colorectal liver metastases, especially when patients have synchronous lesions.