Background: Although studies have described an inverse relationship between sleep duration and obesity, there is limited knowledge about the association between sleep duration and severe obesity in the work place. In this study, we evaluated the relationship between self-reported sleep duration and severe obesity in a large, healthcare employee population. Methods: Employees of Baptist Health South Florida (BHSF), a large nonprofit healthcare organization participated in an annual Health Risk Assessment in 2014, from which data for this study was obtained. Average sleep duration was self-reported while weight, height and other biometric measures were captured in person. Obesity status was categorized as BMI <30, 30 - 34.9 and ≥35kg/m2, while average sleep duration was also categorized (as < 6 hours, 6 - 8 hours and > 8 hours). Results: A total of 10363 participants (mean age 42.8 ± 12.1 years, 75% females, 57% Hispanic) had complete information on the variables of interest. Almost one-quarter (24%) of employees who slept less than 6 hours a day were severely obese, compared to about 13% and 14% of employees who sleep between 6-8 hours and 8 or more hours of sleep respectively. Compared to those who slept for 6 - 8 hours, persons who slept for less than 6 hours had almost a 2-fold increase in odds of severe obesity (OR= 1.9; 1.6 - 2.2). Conclusion: In this large diverse employee population, short sleep duration is associated with a significantly increased risk of severe forms of obesity. Workplace-based programs should be encouraged to place more emphasis on adequate sleep as an important factor associated with weight control and cardiovascular health. Further studies are needed to define a temporal relationship between sleep duration and obesity severity.