Abstract: Objective：To explore the detection results of serum related gene methylation in colorectal cancer patients with liver metastasis. Methods：From hospitalized patients with primary colorectal cancer from September 2011 to December 2013, 32 colorectal cancer patients with liver metastasis and 32 colorectal cancer patients without liver metastasis were selected as the experimental group A (n=30) and experimental group B (n=30), respectively. All patients did not undergo chemotherapy or radiotherapy before admission. In addition, 20 healthy subjects were recruited as the control group. DNA was extracted from serum, and Ecad, ID4, ESR1, APC, and HACE gene methylation were detected by methylation specific PCR method. Results：19 cases with Ecad, ID4, ESR1, APC or HACE abnormal methylation were detected in the experimental group A, 10 cases were detected in the experimental group B, no case was detected in the control group. There were significant differences among the three groups (P＜0.01). Conclusions：〖BP(〗The serum in patients with colorectal liver metastases cancer related gene methylation detection, the joint detection E  cad, ID4, ESR1, APC and HACE genetic abnormalities is important for diagnosis and therapy of colorectal liver metastases. 〖BP)〗Detection of serum Ecad, ID4, ESR1, APC, HACE gene methylation status〖BP(〗 in patients with colorectal cancer liver metastasis〖BP)〗 is of great significance for clinical diagnosis and treatment of colorectal cancer liver metastasis.