Aim: This study was aimed to evaluate the oral health status and knowledge of diabetic and nondiabetic patients attending dental clinic at College of Dentistry, Hail, the Kingdom of Saudi Arabia. Materials and methods: It was an observational cross-sectional study. Using nonprobability convenient sampling technique, data were collected from 202 respondents. A total of 202 diabetic and nondiabetic patients were screened for the study. Data were collected by interview using the structured, self-administered questionnaire, and assessment of oral health status was done by clinical examination. The collected data were analyzed using IBM SPSS software. The data were displayed as numbers and percentages and association among the variable of interests was measured using Pearson Chi-square. Results: Of the 202 patients, 102 (50.6%) were males and 100 (49.4%) were females. Majority of the patients, 71 (35.2%) were in the age-group of 30–40 years. In all, 128 (63.4%) participants knew the effect of diabetes mellitus (DM) on oral health, 167 (82.7%) knew that diabetic patients needed special healthcare, 152 (75.25%) had never spoken to their doctors about oral health, and 164 (81.19%) had never spoken to their dentists regarding diabetes. Conclusion: The complications associated with oral health are more common in diabetic patients when compared to the nondiabetic patients. This is the case in both male and female patients visiting the College of Dentistry in the Hail region. Clinical significance: Diabetes mellitus is associated with increased susceptibility to oral infections especially periodontal disease. Role of a general dentist in diagnosis and raising patient awareness toward DM and its effects on oral health need to be emphasized.