Navigating difficult patient conversations is a core competency of oncologists, yet structured communication training for residents and fellows is lacking. Trainee-targeted interventions have been reported in the literature; however, no systematic review of communication skills education in oncology trainees has been performed. We analyzed the available evidence to understand the breadth and effectiveness of communication interventions in this population. EMBASE and PubMed were queried to identify English language publications examining targeted interventions for pediatric or adult oncology-trainees aimed at improving communication skills with cancer patients. Exclusion criteria included studies without a clear intervention aimed to improve skills, or without an objective measurement of the intervention. Titles, abstracts, and full texts were screened by two independent reviewers, with a third author serving as an adjudicator of conflicts. Relevant data were abstracted and analyzed. Of 811 studies identified, 14 were included, representing 1024 unique trainees (range, 11-262). Three studies were randomized control trials (RCTs) and 11 were longitudinal cohort studies. Populations were heterogenous, including trainees from medical, radiation, hematologic, surgical and pediatric oncology, spanning all post-graduate levels. Only 1 study (n = 11) examined a population of exclusively radiation oncology residents, and showed no significant improvement in pre- and post-intervention scores as assessed by standardized patients. Radiation oncology residents were minimally represented in other studies. Ten different intervention designs were used and included facilitated role-play, multimedia, and didactic components. Time commitment ranged from 1-hour videos to 40 hours of in-person training over 8 months. Intervention arms in all RCTs showed statistically significant improvement in communication domains, including empathy, support, open-ended questions and active listening scores. Self-assessed confidence or skills improved significantly post-intervention in 10/11 studies. Eight studies included assessments by faculty, with 5 showing improvement and 3 showing no significant change. Four studies utilized assessments from standardized patients showing perceived improvement in all. Only one study had evaluation by real patients, and failed to demonstrate improvement. No studies evaluated competency more than 12 weeks post-intervention. Despite variability in interventions, patient communication training for oncology trainees improved perceived performance based on assessments from participants and standardized patients. Opportunities for further study include examining the benefit of specialty-specific training, expanding the breadth of communication scenarios beyond BBN and developing standardized metrics to evaluate the immediate and sustained effectiveness of these programs