To explore the expression of the PIM-1 protein in prostate cancer tissue and its relationship with PSA recurrence.We used the immunohistochemical SP method to detect the expression of the PIM-1 protein in the prostate tissues of 68 cases of prostate cancer (PCa) and 37 cases of benign prostatic hyperplasia (BPH).The positive rate of the PIM-1 protein expression was 67.65% (46/68) in the PCa tissue, significantly higher than 40.54% (15/37) in the BPH tissue (P<0.05). Its positive rates in PCa Gleason scores 6, 7 and 8-10 were 33.33% (7/21), 77.5% (21/28) and 94.74% (18/19), respectively, with significant between-group differences (P<0.05), and those in stages I , II, III and IV of PCa were 47.62%, 53.85%, 73.33% and 94.74%, respectively. Kaplan-Meier analysis of the results of a 36-month follow-up showed the ratios of PIM-1 expression to PSA recurrence and non-recurrence were 10/22 (45.45%) and 36/46 (78.26%), respectively, with statistically significant differences (P<0.05).PIM-1 protein expression in PCa tissue is closely related to the Gleason score and clinical stage of PCa and PSA recurrence, which suggests that the PIM-1 gene plays an important role in PCa evolution and progression, and may be an indicator for the prognosis of PCa.