The study aimed to assess the relationship between coffee intake, obstructive sleep apnea risk (OSA), and glycemic control among patients with diabetes mellitus. There were 110 patients with diabetes and 96 healthy control subjects (matched for age and sex) attending a diabetes center زinTabuk, Saudi Arabia during the period from June 2018–October 2019. Stop-Bang questionnaire was used to assess OSA risk, and Epworth Sleepiness Scale to investigate daytime sleepiness. OSA risk and daytime sleepiness were higher among patients with diabetes compared to controls (4.34 ± 1.61 vs. 2.86 ± 1.24, and 8.31 ± 4.40 vs. 6.39 ± 3.70 respectively, P < 0.5), while coffee consumption was not (4.64 ± 3.95 vs. 3.45 ± 3.06, P > 0.05). Women with diabetes wer.