Abstract: OBJECTIVE To analyze the etiological characteristics, risk factors and diagnostic value of serum surface active protein A (SP-A), surface active protein D (SP-D), urinary heparin-binding protein (U-HBP) and urinary leucocyte esterase (LEU) in patients with urinary tract infection after surgery for prostatic hyperplasia. METHODS A total of 221 patients with postoperative prostatic hyperplasia treated in Haikou Third People's Hospital from Jan 2020 to Nov 2022 were retrospectively collected. Patients were divided into the infected group (29 cases) and the non-infected group (192 cases) according to whether urinary tract infection occurred. Etiological characteristics and risk factors of urinary tract infection after postoperative prostatic hyperplasia were analyzed. Multivariate logistic regression was used to analyze the risk factors for urinary tract infection in patients with postoperative prostatic hyperplasia. The levels of serum SP-A/D, urinary U-HBP and LEU were compared between the two groups. Receiver operating characteristic curve (ROC) was used to analyze the diagnostic value of serum SP-A/D, urinary U-HBP and LEU in patients with postoperative prostatic hyperplasia. RESULTS A total of 37 strains of pathogenic bacteria were detected in 29 patients with urinary tract infection after prostatic hyperplasia, in which 28 strains were gram-negative bacteria, accounting for 75.68% and 9 strains were gram-positive bacteria, accounting for 24.32%. Multivariate logistic regression analysis showed that diabetes mellitus and preoperative catheterization were independent risk factors for postoperative urinary tract infection after prostatic hyperplasia (P＜0.05). The serum levels of SP-A, SP-D and urine U-HBP and LEU positive rate in the infected group were higher than those in the non-infected group (P＜0.05). The value of area under curve (AUC) and sensitivity of combined detection of serum SP-A/D and urine U-HBP levels and LEU positive rate in the diagnosis of urinary tract infection after prostatic hyperplasia surgery were higher than those of individual detection (P＜0.05). CONCLUSION The main pathogenic bacteria of urinary tract infection in patients with benign prostate hyperplasia were Escherichia coli, Enterobacter cloacae and Enterococcus faecalis and many risk factors related to it. The combined detection of serum SPA /D, urine U-HBP and LEU could improve the diagnostic value of urinary tract infection in patients with benign prostate hyperplasi.