The Fear of Sleep Inventory (FOSI) was developed to identify factors that contribute to sleep disturbances in individuals exposed to trauma. This investigation examined the psychometric properties of the FOSI in a sample of African American young adults residing in urban areas. A 5-factor structure was derived from an exploratory factor analysis and then verified by confirmatory factor analysis. FOSI factors were positively correlated with the severity of PTSD (rs = .30 to .58, all ps < .001) and insomnia symptoms (rs = .36 to .64, all ps < .001). Individuals with probable PTSD or insomnia had higher scores on the total FOSI and each of the factors compared to those without probable PTSD (all ps < .001; effect sizes: r = .32 to .62) or insomnia (all ps < .001; effect sizes: r = .42 to .70). These data expand the evidence that the FOSI identifies factors contributing to sleep disturbances in trauma-exposed individuals.