Abstract: Objective: To study the expression and clinical significance of long non-coding RNA prostate cancer gene expression marker 1(lncRNA PCGEM1) and micro RNA-152-3p(miR-152-3p) in colorectal cancer tissues and serum exosomes. Methods: A total of 138 colorectal cancer patients admitted to Wuxi People's Hospital Affiliated to Nanjing Medical University from January 2020 to October 2021 were selected as the colorectal cancer group, and another 90 healthy individuals who underwent physical examination during the same period were selected as the healthy group. The relative expression of lncRNA PCGEM1 and miR-152-3p in serum exosomes,colorectal cancer tissues and adjacent tissues was detected. The relationship between the expression of lncRNA PCGEM1, miR-152-3p in colorectal cancer tissues and serum exosomes and the clinical pathological characteristics and prognosis in colorectal cancer patients was analyzed. The prognostic factors of colorectal cancer patients were analyzed using the Cox regression model. The diagnostic value of lncRNA PCGEM1 and miR-152-3p in colorectal cancer was analyzed by the receiver operating characteristic(ROC) curve. Results: The relative expres-sion of lncRNA PCGEM1 in colorectal cancer tissues and serum exosomes was higher than that in adjacent tissues and healthy group, respectively, while the relative expression of miR-152-3p was lower than that in adjacent tissues and healthy group(P＜0.05). The expression of lncRNA PCGEM1 and miR-152-3p in serum exosomes and cancer tissues was related to TNM stage, differentiation degree, depth of infiltration,lymph node metastasis, and distant metastasis(P＜0.05). The survival rate in the lncRNA PCGEM1 high expression group was lower than that in the lncRNA PCGEM1 low expression group, the survival rate in the miR-152-3p low expression group was lower than that in the miR-152-3p high expression group(P＜0.05). Serum exosomes lncRNA PCGEM1, miR-152-3p, differentiation degree, lymph node metastasis, and depth of infiltration were influencing factors on patient prognosis(P＜0.05). The area under the curve(AUC), sensitivity and specificity of serum exosomes lncRNA PCGEM1 and miR-152-3p in combination were significantly higher than those of each index examined separately(P＜0.05). Conclusion: The expression of lncRNA PCGEM1 is up-regulated and the expression of miR-152-3p is down-regulated in cancer tissues and serum exosomes of colorectal cancer patients. The combination of serum exosomes lncRNA PCGEM1 and miR-152-3p has a higher diagnostic efficiency for colorectal cancer.