Objective: To examine if pharmacological treatment of insomnia varied with patient's gender, ethnic, or both. Methods: This was a cross-sectional study using data from 2004 National Ambulatory Medical Care Survey (NAMCS) by National Center for Health Statistics. We identified visits at which at least one frequently used insomnia prescription was prescribed as defined from the American Insomnia Association. A series of population-based descriptive analyses were performed to estimate the national weighted frequency of each drug. Weighted chi-square statistics were used to compare insomnia drugs uses by patients with different gender and ethnic characteristics. To provide national estimates, all analyses incorporated sample weights and standard errors corrections to adjust for the complex sampling design employed by NAMCS. Results: A total of 910 million outpatient visits were estimated in the US. in 2004. A total of 24.98 million visits at least one insomnia prescription was prescribed including 3.38 million visits(13.6%) with FDA approved benzodiazepine receptor agonist; 8.5 million visits(34.1%) with FDA approved non-benzodiazepine receptor agonist; and 13.1 million visits (52.4%) with antipsychotic medications which is used for insomnia treatment without FDA approved. Female received significant more insomnia prescription than male (16.4 mil. VS. 8.58 mil., P<0.0001). Patients who are Black and Hispanics received less insomnia prescription than those who are white (P<0.0001). Conclusion: The study found a significant gender and ethnic disparities in the use of insomnia prescriptions especially to the use of related costly non-benzodiazepine receptor agonist. The problems of access barriers to health care for the minority population are still significant. The study also provided evidence that the non-FDA approved prescription medications that were used significantly frequent to treat insomnia than currently approved agents. The issue of off-label treatment for sleep has been raised concerns about the adverse effects that develop during the insomnia treatment and limit the efficacy of these medications.