Background: Insomnia is the most common sleep disorder that reduces quality of life. Objectives: Due to side effects of hypnotic drug and the increasing demand for alternative medicine substitutes, violet oil (VO) was used in this study. VO is a known medication in Iranian traditional medicine that induces sleep in insomniac patients. Patients and Methods: This study was conducted as an experimental pretest-posttest evaluation on VO efficacy in 50 patients with chronic insomnia in Iranian Traditional Medicine Clinic of Mashhad University of Medical Sciences, Mashhad, Iran. Treatment consisted of intranasal drop of VO, two drops containing 66 mg of VO in each nostril nightly before sleeping for one month. All patients were asked to complete an Insomnia Severity Index (ISI) questionnaire before the start of the trial and after one month of treatment. Results: Improvements in sleep and ISI scores were significantly greater in patients after a month receiving VO drop in comparison with before starting treatment (P < 0.05). A few patients reported some complications about VO consumption, most of which were mild and no serious adverse event was encountered. Conclusions: VO can be presented as a safe, well-tolerated, and effective herbal preparation in patients with chronic insomnia.