PURPOSE: Regular monitoring of serum carcinoembryonic antigen (CEA) has been used as a tool to detect recurrence of colorectal cancer postoperatively. This study aimed to evaluate the significance of perioperative serum CEA level in patients with curative colorectal cancer. METHODS: We analyzed the data obtained from the 420 patients with colorectal cancer who underwent curative resection. Preoperative serum CEA level (ng/ml) was divided into 3 groups, i.e. groups I: or=20. Each group of preoperative serum CEA level was analyzed in accordance with location, histologic differentiation, stage of tumor, recurrence and survival. Postoperative serum CEA level was analyzed in accordance with preoperative serum CEA level and recurrence. RESULTS: Preoperative serum CEA level correlated with tumor stage (P=0.009). Ninety six patients among 420 patients showed recurred and recurrences were more common in patients with high preoperative serum CEA level (P =0.002). Systemic recurrences were more common in patients with high preoperative serum CEA levels than normal levels (P=0.029). In recurrence cases, 75 patients (78.1%) had elevated serum CEA levels and 55 patients had high preoperative serum CEA levels (P=0.008). The disease free 5-year survival rate in preoperative serum CEA group I, II, and III were 91.4%, 70.5%, and 58.3% respectively (P= 0.000) CONCLUSION: Preoperative serum CEA levels seemed to be closely correlated with distant metastasis and survival. Meticulous follow-up evaluation and generous use of adjuvant therapy are recommanded in patients with high preoperative CEA level.