Objective: The objective of this study was to investigate the association between chronic diseases and sleep difficulty in older women. Method: A total of 10,721 women from The Australian Longitudinal Study on Women’s Health, aged 70 to 75 years at baseline (1996), who answered sleep questionnaire data over 15 years follow-up, were surveyed. Longitudinal sleep difficulty class was regressed on baseline diseases. Results: Arthritis and heart disease were the strongest predictors of sleep difficulty; odds ratios for belonging to the greatest sleep difficulty class were 2.27 (95% confidence interval [CI] = [1.98, 2.61]) and 1.8 (95% CI [1.5, 2.16], respectively. Bronchitis/emphysema, osteoporosis, asthma, diabetes, and hypertension also predicted greater sleep difficulty. Conclusion: Older women diagnosed with the aforementioned significant diseases may also be at greater risk of sleep difficulty. These women may need counseling or treatment for their sleep difficulty, to prevent depression, cognitive function decline, falls, frailty, and increased mortality, as well as greater risk of nursing home placement, well known to be reinforced by sleep trouble, and the associated health care costs and societal impacts poor sleep quality has for older adults.