Introduction Organizing pneumonia (OP) is an uncommon clinic opathological situation among lung diseases. If no underlying cause can be detected, it is named as cryptogenic OP (COP). In this study, the etiologic and clinical characteristics of patients diagnosed as OP in our hospital in the last ten years were evaluated retrospectively. It was also aimed to make a comparison between COP and secondary OP patients. Materials and methods One hundred sixty-five patients diagnosed as OP pathologically in the 10 year period from August 2003 to August 2013 were included into that study. Patients' data were evaluated retrospectively from the medical records. Result One hundred sixty five patients pathologically diagnosed as OP were included. Diagnostic methods were trans-thoracic fine-needle biopsy (TTFNB) in 89 (53.9%) patients, open lung biopsy (lobectomy, wedge resection, segmentectomy) in 52 (31.5%) patients and transbronchial biyopsy (TBB) in 24 (14.5%) patients. One hundred (60.6%) of the patients were defined as COP and 65 (39.4%) as secondary OP. Cough, fatigue and dyspnea were the most common symptoms on admission. We detected OP cases secondary to anthracosis and cyst hydatic besides other well known etiologies. In 61 patients, the main radiologic manifestation was multiple bilateral patchy consolidation typical for OP. In 76 patients focal lesions (solid mass, cavitating mass lesion) and in 6 patients infiltrative opacities were detected radiologically. Conclusions There is no difference between properties of OP from clinical, laboratory and radiologic finding sin the criptogenic and seconder form of OP. Although it is not asserted, cyst hidatic and anthracosis could be kept in mind for the list of underlying ethiologies for secondary OP.