Background: Clinical governance (CG) serves as a crucial mechanism for enhancing service quality in primary health care (PHC) facilities in Egypt. Little is known about knowledge of PHC physicians about CG. The aim of this study was to assess the knowledge of PHC physicians about the concepts of CG and to identify its determinants. Methods: A cross-sectional study was conducted on 108 PHC physicians selected through a convenience sampling technique. The data were collected through a validated questionnaire including data related to knowledge of PHC physicians about the concepts, principles of CG, and barriers affecting their engagement in CG. Binary logistic regression analysis was used to detect the predictors of knowledge about CG. Results: More than half of participants (52.8 %) had high knowledge about CG with a total mean score of (3.61 +/- 0.73). 65.7 % and 61.1 % of PHC physicians knew continuous quality improvement (CQI) and responsibility as CG principles, respectively. Multiple regression analysis revealed that those with diploma (AOR = 9.72, P = 0.007), those who had postgraduate studies (AOR = 3.99, p = 0.007), and those who previously heard about CG (AOR = 5.78, P = 0.019) significantly predicted PHC physicians' knowledge of CG. Conclusion: More than half of PHC physicians are knowledgeable about CG. Level of education is the strongest predictor of PHC physician's knowledge. Less than half of rural physicians have high knowledge about CG, and no statistically significant difference has been detected. Thus, conducting educational and training programs, and increasing human and financial resources are crucial for improving PHC physicians' engagement in CG.