Objective：To explore the clinical significance of Ras and a-factor converting enzyme 1（Rce1） in the diagnosis of prostate cancer（PCa）. Methods：Blood samples from 96 patients with PCa and 133 patients with benign prostatic hyperplasia（BPH） as con－firmed by pathology from April 2017 to October 2018 were collected for Western blot and enzyme-linked immunosorbent assay （ELISA）. Meanwhile，another 30 patients with urinary calculi，cryptorchidism，and varicocele were treated as normal control group. Then levels of Rce1 in the blood specimens from these groups were analyzed to evaluate its performance in the diagnosis of PCa. Results：The PCa group had a significantly higher level of Rce1 compared with those of the BPH group and normal control group（93.25±15.14 pg/μL vs. 78.37±16.91 pg/μL and 77.73±12.04 pg/μL，P=0.000）. However，there was no significant difference between the BPH and normal control group regarding the level of Rce1（P=0.843）. Meanwhile，the level of Rce1 was positively cor－related with Gleason score and N stage（P=0.030，P=0.039）. With the optimal cut-off value of 74.98 pg/μL，Rce1 had a sensitivity of 89.7% and a specificity of 46.3%. The area under the receiver operating characteristic curve of combined diagnosis with Rce1 and prostate specific antigen（PSA） was higher than each diagnostic method alone（P=0.000）. Conclusion：Blood Rce1 test is helpful to improve the early diagnosis rate of PCa，and Rce1 combined with PSA also can improve the diagnostic efficiency of PCa. Therefore，Rce1 is deemed as a new marker for the screening for and prognosis of PCa.