OBJECTIVE/BACKGROUND: Sleep problems are common in people on the autism spectrum. This study reviews one detailed approach to querying the electronic health record (EHR) in a large tertiary care center. PATIENTS/METHODS: We developed methods for identifying people on the autism spectrum and defined their sleep problems using the key words, “sleep” or “melatonin”, or International Classification of Diseases (ICD) codes. We examined treatment responses of these individuals to melatonin supplementation. RESULTS: Sleep problems were documented in 86% of patients with ages ranging from 6–30 years old. Our specific keyword search yielded more patients with sleep diagnoses than ICD codes alone. About two-thirds of patients who received melatonin supplementation reported benefit from its use. CONCLUSIONS: Our study provides a framework for using deidentified medical records to characterize sleep, a common co-occurring condition, in people on the autism spectrum. Using specific keywords could be helpful in future work that queries the EHR.