Polycystic kidney disease in adults may be a multisystem disorder. Its association with seminal vesicle cysts is very rare. This is a report of two patients where the diagnosis was made by imaging with transrectal ultrasound and magnetic resonance. A discussion of the differential diagnosis is presented. Since both patients presented with infertility, it is presumed that involvement of the seminal vesicles was responsible for this. The overall pathogenetic mechanism of the disease is discussed.