Immunophenotyping of blood cells allows the completion of the malignant lymphoma cell line and the area of damage. Diagnosis of malignant B-cell lymphomas can be established with certainty by immunophenotyping and immunohistochemistry. Further investigation of cytogenetic and molecular biology are mandatory for a complete diagnosis. Immunophenotyping is absolutely essential in the current diagnosis of lymphoma as their new classification is based on the determination of line B or T / NK on the phase of differentiating malignant lymphomas and the area of damage. Our study group consists of 122 patients with undetermined non-Hodgkin malignant lymphoma, 120 cases of lymphoma, B-cell malignancies (98, 3%), and only in 4 (3, 3%) cases, the T-cell line was detected. The research feature was broadly overlapped with literature data that 90% of cases of malignant lymphoma are Bcell lymphomas and 10% are from cell line T. The evaluation of cellular immunophenotype, the first indirect method of labeling lymphocytes with monoclonal antibodies, is undoubtedly an important part of the diagnosis of lymphoid neoplasm. It has been determined that a series of antigens expressed on the surface of the malignant cell may have prognostic significance, which may influence the progression of the disease and its response to treatment.