Background: The provision of sick leave to patients in general practice often entails a complex decision-making process. Commonly, general practitioners believe that the act of providing sick leave can become confrontational. We assessed the intention, attitude, subjective norm, and perceived behavioral control of general practitioners in relation to sick leave provision at public health clinics in Malaysia. Methods: A cross-sectional study design was implemented using data from 86 primary health care clinics in two states in Malaysia from February 2014 to March 2015. A questionnaire that comprised indirect measures were developed on the basis of the Theory of Planned Behavior. The questionnaire assessed several dimensions related to sickness certification provision viz., intention, attitude, subjective norm, and perceived behavioral control. Results: The mean scores in this study revealed that physicians acknowledged that patient factors such as clinical symptoms (6.59±0.04), debilitating signs and symptoms of diseases (6.45±0.06), importance of illness recovery (6.07±0.07), and approval of employers (5.35±0.09) played an important role in their decision to provide sick leave. Conclusion The act of providing sickness certification to patients is a complex decision-making process. The findings of this study can be used to devise a targeted intervention to reduce the conflict that physicians face in issuing sick leaves.