The pleural empyema has unusual origin at extralung causes. Then, is essential to identify the primary process in order to obtain the clinical setting control. Previously described, but even exceptional, this case report show an empyema in which it's origin was an asymtomatic pyonephrosis, caused because of a big kidney calculus and it's discovery was suspected by the bacillus results. The treatment must include appropriate antibiotic therapy and thoracic drainage, and also the drain of the purulent accumulations at the kidney and perikidney area.