This study aims to explore the impact of extrinsic and intrinsic factors on the counseling competence of Vietnamese school counselors. A cross-sectional study was conducted on 226 teachers in two Vietnamese provinces. All school counselors have attended school counseling training courses with an average experience of 11.3 years. Linear regression analysis was used to determine the impact of extrinsic and intrinsic factors on counseling competence. The results show that: (i) When considering separately the impact’s possibility of each factor, the model has confirmed the possibility of a positive impact of both factors; (ii) however, when considering the model combining two groups of factors, the role of variables in the extrinsic factors no longer exists, while the role of variables in the intrinsic factors is still available. This study has confirmed the role of intrinsic factors related to the personal counseling competence of school counselors. This finding allows us to propose a solution to improve and develop counseling competence for school counselors focusing on identified intrinsic factors and promoting policies to maintain the positive impact of extrinsic factors in Vietnamese education or countries with similar educational backgrounds.