Background Oncology and hematology is a complex and specific area that requires monitoring by a multidisciplinary team capable of personalizing the treatment of each patient. Clinical pharmacy services have the potential to contribute significantly to the effective and economical care of cancer patients. Objective To evaluate, synthesize and critically present the available evidence on the impact of the Clinical Pharmacy in the treatment of patients with hematological cancer. Method A review was carried out on the bases PubMed/MEDLINE, LILACS and Google Scholar. The included studies were: studies that evaluated the effects of pharmaceutical interventions in clinical in oncology and hematology services and having as a population patient with hematological cancer. Results 17 studies were selected among 745 identified. 4.771 patients were included, with an average follow-up time of 15.3 months. Patients affected by some type of hematological cancer, undergoing chemotherapy treatment, showed better adherence and continuity when accompanied by a clinical pharmacist, added to this professional in carrying out interventions, provides control of symptoms such as cancer pain, nausea and constipation and, thus, contributes to decrease the length of hospital stay. Conclusion The implementation of a Clinical Pharmacy service in oncology and hematology centers contributes significantly to the effectiveness of pharmacotherapeutic treatment, treatment costs reduction, safety increase in the use of medications and the patient’s quality of life.