Gynecomastia is the most common definition of breast tissue growth. It is common in urology due to androgen blockade used in prostate cancers. Clinically insignificant gynecomastia is present in 50% of men and there is no proliferation of breast tissue in ductus epithelium. Gynecomastia is rarely seen in primary testicular tumors such as Leydig Cell Tumors (LCT). Leyındg Cell Tumors are one of the rare sex cord stromal cell tumors of the testis . Although it is usually with endocrine changes, it is a painless mass or incidentally occurring tumor in the testis. In this case report, we examined the left testicle cell tumor of the gynecomastia at the age of 43 years. He had been admitted to our clinic for gynecomastia and breast pain for 6 years. The patient was followed-up by endocrinology due to the aforementioned complaints. The patient was suspected of prolactinoma. Physical examination revealed no MRI. MRI, heterogenous hyperintense in T2A with mild lobulated contoured T2A with a hypointense capsule in T2A with well limited T2A in the left intratesticular area, and heterogeneous isohaphy hyperintense internal T1A in the form of a nodular lesion (testicular tumor) showing intense and heterogeneous contrast enhancement commented. The patient underwent left inguinal orchiectomy and the pathology report was negative for the leyding cell tumor and surgical margin. Leydig cell tumors are the most common spermatic cord / stromal tumors. About 30% of patients present with gynecomastia. Ultrasonography is accepted as the first research method for the diagnosis of leydic cell tumor, but MRI is superior to ultrasonography in diagnosis. The gold standard treatment option is radical inguinal orchiectomy. The mechanism of hormonal disorders may be an overproduction of testosterone and estrogens by the tumor. As in our case, it is necessary to consider the possibility of LCT which is rarely seen in patients with gynecomastia and to provide differential diagnosis by performing the tests in this direction.