Background The electronic health record (EHR) is a contributor to serious patient harm occurring within a sociotechnical system. Chemotherapy ordering is a high‐risk task due to the complex nature of ordering workflows and potential detrimental effects if wrong chemotherapeutic doses are administered. Many chemotherapy ordering errors cannot be mitigated through systems‐based changes due to the limited extent to which individual institutions are able to customize proprietary EHR software. We hypothesized that simulation‐based training could improve providers’ ability to identify and mitigate common chemotherapy ordering errors. Methods Pediatric hematology/oncology providers voluntarily participated in simulations using an EHR testing (“Playground”) environment. The number of safety risks identified and mitigated by each provider at baseline was recorded. Risks were reviewed one‐on‐one after initial simulations and at a group “lunch‐and‐learn” session. At three‐month follow‐up, repeat simulations assessed for improvements in error identification and mitigation, and providers were surveyed about prevention of real‐life safety events. Results The 8 participating providers identified and mitigated an average of 5.5 out of 10 safety risks during the initial simulation, compared 7.4 safety risks at the follow up simulation (p=0.030). Two of the providers (25%) reported preventing at least one real‐world patient safety event in the clinical setting as a result of the initial training session. Conclusions Simulation‐based training may reduce providers’ susceptibility to chemotherapy ordering safety vulnerabilities within the EHR. This approach may be used when systems‐based EHR improvements are not feasible due to limited ability to customize local instances of proprietary EHR software.