ObjectiveExercise during and after cancer treatment has established quality of life and health benefits. However, particularly for patients with hematological cancer clear recommendations regarding the safety and feasibility of exercise are under-investigated. The aim of our systematic review was to summarize the literature regarding the feasibility and safety of exercise interventions in patients diagnosed with hematological cancer undergoing chemotherapy.MethodA systematic literature review was conducted using PubMed, SPORTDiscus, MEDLINE, Science Direct, and Web of Science electronic databases. Eligible studies were scientific publications reporting the feasibility and/or safety of an exercise intervention program carried out in inpatient patients diagnosed with hematological cancer undergoing chemotherapy.ResultOut of 12 studies (six RCTs) included in this review, six investigations reported results with regard to safety and 10 with regard to feasibility. While all studies claim that their exercise interventions were safe and/or feasible, it is noteworthy that this claim often remains unsupported as detailed information on how the feasibility of the intervention was asserted is missing.ConclusionExercise appears to be safe and feasible in hematological cancer patients. However, due to a striking lack of information on how the feasibility of the intervention was asserted, contextualizing the results and deducing recommendations for further studies remains challenging. Further research should therefore incorporate information on the execution of the exercise intervention in more detail.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00520-023-07773-9.