To assess barriers to patients with mental illness receiving oral healthcare in Makkah city, Saudi Arabia. Methods: This was a 3-month cross-sectional study from the Department of Psychiatry at Al-Noor, Specialist Hospital in Makkah city, Saudi Arabia, between January 2017 and April 2017. A structured questionnaire with closed-ended questions was considered. A total of 161 psychiatric patients were recruited, made up of 81 male (50.3%) and 80 female (49.7%) participants. Simple descriptive statistics were used to define the characteristics of the study variables, through a form of counts and percentages. The chi-square test was also used to evaluate the distribution of the nominal variables. Results: Of the 161 psychiatric patients, 51 were aged 26-35 years old (31.7%). Most participants (n=73) had psychological development disorders (45.3%). Ninety-one (56.5%) were unemployed, and among them, 25 (15.5%) reported problems with access to oral health and dental care. Participants also suffered from dry mouth (64%) and dental anxiety (23%). Conclusions: This study suggested that dental anxiety is considered the major barrier to dental care, followed by the cost of dental treatments and accessibility. Most belonged to the group of psychological development disorder and reported having the most barriers to oral healthcare.