Striatin-4 (STRN4 or Zinedin) is a scaffolding protein belonging to the mammalian STRN family of proteins and consists of multiple functional signaling domains. Due to its numerous signaling complexes, STRN4 has been reported to be involved in the tumorigenesis of various cancer types, including colon cancer, liver cancer and prostate cancer. However, few studies on STRN4 have been conducted in bladder cancer, and its prognostic role in bladder cancer remains unknown. The present study aimed to investigate the expression levels of STRN4 in bladder transitional cell carcinoma and evaluate the prognostic role of STRN4. STRN4 expression in clinical specimens was analyzed using immunohistochemistry and reverse transcription-quantitative PCR. It was demonstrated that STRN4 expression was significantly associated with clinical parameters such as tumor size, muscle invasion depth and pathological tumor grade. Abnormal STRN4 expression was typically associated with worse overall survival time and outcome when compared with the low STRN4 expression group. Using multivariate analysis, it was reported that STRN4 was an independent prognostic biomarker for survival time in bladder transitional cell carcinoma. Although the specific biological mechanisms of STRN4 in bladder cancer still remain to be elucidated, STRN4 expression could be a prognostic indicator in bladder cancer.