Background: Insomnia and sleep-disordered breathing (SDB) are the most common sleep disorders among midlife women. Although promoting sleep hygiene behaviors may be a useful behavioral approach for the management of insomnia or SDB, the frequency with which women engage in these behaviors is unclear. Methods: Participants were from the Study of Women's Health Across the Nation (SWAN) Sleep Study (N = 321; age range = 48-58 years). Out of the full sample, 10.3% (n = 33) met Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition diagnostic criteria for insomnia, 15.3% (n = 49) had clinically significant SDB (apnea-hypopnea index ‡ 15), and 4.7% (n = 15) met criteria for both insomnia and SDB, resulting in an overall prevalence of 15.0% (n = 48) for insomnia and 19.9% (n = 64) for SDB. Participants provided diary-based assessments of sleep hygiene behaviors for 14-35 days. Two positive behaviors (sufficient exercise, regular morning out-of-bed time) and four negative behaviors (taking long daytime naps, caffeine consumption near bedtime, alcohol consumption near bedtime, smoking) were examined. These behaviors were compared between women with and without insomnia or SDB following adjustment for sociodemographic factors and mental and physical health indices. Results: Women with insomnia engaged in significantly fewer negative sleep hygiene behaviors than women without insomnia (1.61 -0.15 vs. 2.09 -0.09 behaviors; p < 0.01); specifically, women with insomnia were less likely to take long naps (odds ratio [OR] = 0.30, 95% confidence interval [CI]: 0.12-0.74) or consume caffeine near bedtime (OR = 0.44,. In contrast, women with SDB were less likely to be physically active than women without SDB (OR = 0.52, 95% CI: 0.27-0.98), but no other differences in sleep hygiene behaviors were observed. Conclusions: These data suggest that insomnia in midlife women is not associated with poor sleep hygiene. Increasing physical activity may be a valuable recommendation for midlife women with SDB.