Clinical guidelines for the care of obstructive sleep apnea (OSA) recommend evaluation of daytime sleepiness but do not specify evaluation of fatigue. We studied how subjects with and without OSA experience fatigue and sleepiness, examining the role of gender and race. Consecutive subjects entering our heart health registry completed validated questionnaires including Berlin Questionnaire for OSA, Fatigue Scale, and Epworth Sleepiness Scale. Data analysis was performed only with Whites and Blacks as there were too few subjects of other races for comparison. Of 384 consecutive subjects, including 218 women (57 %), there were 230 Whites (60 %) and 154 Blacks (40 %), with average age of 55.9 +/- 12.8 years. Berlin Questionnaires identified 221 subjects (58 %) as having high likelihood for OSA. Fatigue was much more common in women (75 %) than in men (46 %) with OSA (p < 0.001), while frequency of fatigue was similar in women (30 %) and men (29 %) without OSA (p = 0.86). In multivariate analysis, men with OSA were sleepier than women; Black men with OSA had higher Epworth scores (mean +/- SD, 12.8 +/- 5.2) compared to White men (10.6 +/- 5.3), White women (10.0 +/- 4.5), and Black women (10.5 +/- 5.2), p = 0.05. These gender differences were not related to the effects of age, body mass index, perceived stress, sleep duration, or thyroid function. Women report fatigue more commonly with OSA than men. Men experience sleepiness more commonly with OSA than women. The findings suggest that evaluation of sleep disorders must include an assessment of fatigue in addition to sleepiness to capture the experience of women.