Introduction: Self-care programs can raise health in patients with Multiple Sclerosis (MS). This study aimed to identify the self-care behaviors and determinants in patients with MS according to the Health Belief Model (HBM). Methods: In this cross-sectional study, we included 280 MS patients through convenience sampling method. The collection tool was a self-administered questionnaire based on HBM. The participants were the members of MS society in Kerman, Iran. The data were analyzed using descriptive statistics, path analysis, and multivariable linear regression in SPSS software Version 22. Results: The mean (SD) score for self-care practices was 2.86 (0.64), and medication adherence was the most conducted practice. The perceived benefits and cues to action exerted positive influence on self-care practices. The most frequent symptoms experienced by the participants were fatigue (82.5%), visual impairment (76.4%), headaches (72.1%), and muscle weakness (71.4%). The most important cues to action for self-care behavior were the physician (77%), media (52%), and other MS patients (32%). Conclusion: The quality of life (QOL) of MS patients is heavily influenced by self-care behaviors. In this study, only about half of the patients accomplished self-care behaviors, which seems to be insufficient. Since the perceived benefits and cues to action are the main predictors of self-care practices, intervention based on these two constructs can be utilized to promote self-care programs and QOL in MS patients. Health-care providers should pay more attention to these factors for promoting self-care behaviors.