[Abstract] Objective:To investigate the relation between mRNA expression of CCAT-1 in the peripheral blood, clinicopathological features and prognosis of patients with colorectal carcinoma. Methods: Real-time quantitative polymerase chain reaction (qPCR) was performed to detect CCAT-1 mRNA expression levels in patients with colorectal carcinoma (60 cases) and colorectal adenoma (30 cases) as well as healthy volunteers (30 cases). The value of CCAT-1 in diagnosis of colorectal carcinoma was evaluated by ROC curve, diagnosis threshold of CCAT-1 mRNA level in colorectal carcinoma was determined by Youden index. Bivariate correlation analysis was performed to analyze the correlation of the expression levels of CCAT-1 and clinicopathological features in patients with colorectal carcinoma. Kaplan-Meier survival curve was performed to analyze the correlation between CCAT-1 expression and survival of patients with colorectal carcinoma. Results: CCAT-1 mRNA expression levels in patients with colorectal carcinoma were significantly higher than those in patients with adenoma (P < 0.01) and healthy volunteers (P < 0.01). CCAT-1 mRNA expression levels were positively correlated with the diameters of tumor, grade of differentiation, invasion depth of primary tumor, the number of lymph node and distant metastasis (P < 0.05) and TNM stage (P < 0.01), and were negatively correlated with survival time (P < 0.05). The survival time of patients with colorectal carcinoma with higher-level CCAT-1 expression was significantly shorter than that of the lower-level group. Conclusion: CCAT-1 can be considered as a valuable marker for early screening and prognosis assessment of colorectal carcinoma.