An educational program using Radiation Oncology-Incident Learning System (RO-ILS) was developed to improve safety culture and training for radiation oncology (RO) residents. The program included a pre-training assessment, interactive training, integration of residents into quality assurance meetings, and a post-training assessment over a 3 month rotation. Twelve residents completed the safety training program. Pre-training assessment mean scores (five-point scale) of experience with Incident Learning Systems (ILS), root-cause analysis (RCA), failure-mode and effect analysis (FMEA), safety training, and culture were 2.3, 2.8, 2.0, 4.0, and 4.4, respectively. Post-training assessment showed a significant increase in ILS 4.0 (p<0.001), RCA 3.8 (p=0.008), and FMEA 3.3 (p=0.006) and safety culture (4.8, p=0.043). Additionally, residents were anonymously surveyed ≥ 10 months after graduation to determine the long-term value of the program. The overall assessment from the graduated residents indicates that this education is valued by RO in many institutions. The majority of the residents are either currently utilizing or plan to utilize the information gained in this program in their new institutions. We report a successful implementation of a safety training program in a RO residency with significant improvements in self-reported confidence with the concepts of ILS, RCA, and FMEA and an improved perception of safety culture. This program can be implemented across all residency programs.