We report a case of bobby hair pin foreign body as a nidus for the inf
ormation of a large vesical calculus, Presentation of the case was unu
sual and the discovery of calculus on foreign bdy was a chance finding
. Approximate duration of insertion of foreign body into the bladder s
hould have been 8 to 10 years. Psychosomatic changes of the patient ar
e considered to be due to her chronic urinary illness, which slowly im
proved after surgery.