The aim of the present study is to evaluate the knowledge, attitudes, and behaviors of dental students on oral cancer in Istanbul, Turkey. A self-administered questionnaire adapted from Tanriover et al. consisting of 48 questions was distributed to 311 students enrolled in the fourth and fifth grades of a dental faculty in Istanbul, Turkey. Questions were grouped under 5 main headings: socio-demographic features, knowledge on risk factors and diagnostic procedures, history taking regarding to alcohol and smoking status, opinions and behaviors of oral cancer, and distribution of dental students according to diagnostic practice of oral cancer. The frequencies and percentages were calculated with descriptive analysis. The differences in distributions were analyzed using the chi-squared test. The p value was set at 0.05 for statistical significance. The overall response rate was 98% (305/311). The majority of the students identified tobacco and alcohol as risk factors (82% and 75.1%, respectively), while older age and inadequate consumption of fruits and vegetables were less likely to be known (60.2% and 52.8%, respectively). Almost one-fifth of the students stated that they have never performed oral cancer examinations during their first or subsequent dental examinations of their patients. Female students thought that dentists were authorized to make oral cancer examinations with a higher frequency compared to males (65.8% and 34.2%, respectively; p = 0.006). On the other hand, female students reported that they did not receive adequate education regarding cessation of smoking with a higher frequency compared with males (69.2% female and 30.8% male respectively; p = 0.0001). As this present study revealed that future dentists had insufficient knowledge in some of the main concepts on oral cancer risk factors, and they lacked the confidence in performing oral examinations in their patients, it is concluded that there is a need for a more structured teaching program with greater emphasis on the early signs and risk factors of OC. Reorganization of the dental curriculum, and courses which further draw attention on the responsibility of the dental practitioner in the detection of oral cancers will be beneficial for the creation of awareness on this significant topic among future dental workforce. Understanding the knowledge and perception of dental students on oral cancers is not only limited to a specific country but it is a worldwide critical issue in which information should be exchanged.