Background: Dystrophic calcification (DC) can occur as a reaction to tissue damage and necrosis. So far, this has never been described as a complication after conventional transurethral resection of the prostate (TURP). Case Presentation: We report on a 59-year-old man who underwent uncomplicated monopolar TURP for lower urinary tract symptoms caused by benign prostatic hyperplasia. The patient showed an excellent course up to 5 weeks after the initial operation. Afterward he suffered from a rapid onset of irritative and obstructive voiding symptoms and pain. Complete DC of the prostatic resection cavity was found by cystoscopy and recurred quickly twice after Re-TURP despite anti-inflammatory treatment and normal urinary and metabolic findings. Complete recovery was only achieved by gently scraping off the calcifications avoiding further trauma to the residual prostatic tissue. Conclusion: In rare cases, delayed occurrence of irritative and obstructive voiding symptoms after TURP can be caused by DC of the prostatic resection cavity and might be misinterpreted as post-TURP infection. The pathomechanism of DC and the presented case suggest minimizing tissue trauma by cautious removal of calcifications rather than performing extensive Re-TURP.