Background: Physicians' attitude towards mental illness is crucial in providing the service and in the feasibility of integrating mental health in primary health care (PHC). Objective: This cross-sectional study aimed to assess PHC physicians' attitudes toward mental illness and integrating mental health services into PHC facilities Material and Methods: This is a cross-sectional study conducted on 105 primary health care physicians in Fayoum governorate, Egypt. For data collection, a self-administered questionnaire was used. It covers three themes: the basic characteristics of the physicians, their attitude towards mental illness using the Mental Illness Clinicians' Attitudes Scale version 4 (MICA 4).  and their attitude towards integrating mental health into PHC.  Results: The mean MICA score was 44.4 ± 8.1 out of 96. A significant positive attitude was found among those younger than 40 years, females, urban residents, those with no postgraduate degree, and those working in an urban PHC facility. The mean score of attitude towards integrating mental health in PHC was 7.02± 2.03 out of 15. The majority of respondents (87.6%) believe in the necessity of integrating mental health in PHC. Conclusion: Physicians' attitude was generally positive regarding mental illness and mental health integration in PHC. Further research is required to identify obstacles in integrating mental health in PHC.