Objective: This study was conducted to compare attitudes and to examine the variables related to the attitudes and attitudes of health professionals in a psychiatric hospital and the general public towards individuals who use substances. Methods: The study was carried out as a descriptive cross-sectional study. The sample study included 212 healthcare professionals employed in a psychiatric hospital and 427 individuals representing the general public. The study data were obtained by using the Introductory Information Form, the Attitudes Toward Treatment of Substance Use Disorders Scale, and the Attitudes and Behaviors of the Society Towards Individuals Using the Addictive Substances Scale. Results: In this study, it was determined that marital status, number of children, educational status, and alcohol consumption related to the attitude. The attitudes of healthcare professionals towards addiction treatment were determined to be positive. When the attitudes scores of an average of healthcare professionals (80.23±19.10) and the general public (91.40±17.76) were compared, a statistically significant difference was found according to the T-test results. Conclusion: The results of this study can increase awareness about the level of attitudes of health workers and the general public toward individuals who use substances. By considering the results of this study, educational activities can be planned to reduce negative attitudes. Individuals who do not or rarely use alcohol, individuals with a low level of knowledge, and those with relatives with substance use disorder can be encouraged to participate more in these training activities. It is recommended to review motivations, the working conditions, and the training curriculum of nurses, and in-depth investigation of the variables that cause the public’s negative attitude.