Cysts of the prostate or perioprostatic tissues are uncommon and include congenital müllerian or utricular cysts, prostatic retention cysts, cysts of benign prostatic hyperplasia, cystic carcinoma, parasitic and infectious cysts, as well as cysts of the ejaculatory apparatus or seminal vesicles. The radiological diagnosis of prostatic or periprostatic cysts can be difficult because of the resolution needed to define the relationship of a cyst to surrounding structures, such as the vas deferens, seminal vesicles, and ejaculatory ducts [1]. Prostatic cysts are easily identified on MR images by virtue of their high signal on T2-weighted images and can be characterized because of their typical locations and the high resolution and multiple imaging planes provided by MR [2]. Because these conditions are usually managed conservatively, pathologic proof is not possible in all cases, and the diagnosis is often made on the basis of clinical features and imaging appearance. The purpose of this essay is to illustrate the findings on MR imaging.