Introduction: Pheochromocytoma is one of representative of neuroendocrine tumors. According this fact, pheochromocytoma remains to evaluation for multiply endocrine neoplasia, especially if disease is bilateral. In this case, it is necessary to additionally carry out a genetic screening test. The aim of the study is to Improve diagnosis and treatment outcomes for patients with MEN syndrome. Materials and methods: The authors present a clinical case of a 37-year-old man diagnosed and treated for a bilateral pheochromocytoma. Results: The patient was diagnosed medullary thyroid cancer after successful bilateral adrenalectomy. The patient underwent thyroidectomy. A genetic research showed the T1900 mutation in the codon of 634 RET gene, which confirmed the presence of the patient MEN 2 syndrome. According to the high concordance of the mutated gene, patient's son was carried out to genetic examinations, which confirmed the presence of this mutation. The boy underwent thyroidectomy opportunely. Discussion: Due to primary oncological observation if the patient has pheochromacytoma, it is necessary to exclude MAN 2 syndrome both in the patient himself and his relatives. The safest and informative method is genetic research. Conclusion: presently a comprehensive examination of both the patient himself and his relatives is necessary for timely diagnosis and correct management of treatment patients with MEN 2 syndrome.