Introduction. Gossypiboma or textiloma is used to describe a retained surgical swab in the body after an operation. Intraabdominal surgical sponge is an uncommon surgical error. The incidence of gossypiboma has been reported as high as 1 in 1000 to 15,000 intraabdominal operations. Gossypiboma may cause serious morbidity and may lead to mortality. Case presentation. Herein, we report a 24 years-old man who was admitted due to the intraabdominal mass after evaluation of primary infertility. He had a surgical history of bilateral abdominal orchiopexy 5 years previously, performed at another hospital. Hydatid cyst was suspected by abdominal computed tomography. After laparotomy excision, the cyst wall opened incidentally, and draining of a large amount of thick pus with retained surgical gauze within the cyst was found, with final diagnosis of gossypiboma. Conclusion. The policy that prevention is far more important than cure is highly appreciated. Accurate sponge and instrument counts, along with radiologic evaluation when a discrepancy is found, can be helpful. Although human errors cannot be completely avoided, continuous medical training and strict adherence to rules of the operation room should reduce the incidence of gossypiboma to a minimum. Surgical sponges should be counted once at the start and twice at the end of all surgical operations.