Private schools are working tirelessly to provide a quality education without support from the government. This article aims to evaluate the internal and external job stress of high school teachers in private schools in Leyte, Philippines, and determine its governing factors. The study involved a complete enumeration process in selecting the participants and gathering primary data. In analyzing and extracting relevant information from the data, standard descriptive metrics, correlation analysis, and Chi-square test for independence were employed with the aid of statistical software. The findings of the study depicted that private teachers are both internally and externally moderately stressful in their jobs. The Chi-square test revealed that employment status and years in service are associated with the private teachers’ internal job stress and it is significant at a 10% level. In addition, it is depicted that gender, monthly salary, and years in service are significantly dependent on the teachers’ external job stress at a 10% level. Conclusively, the school heads and management of private schools must lessen the work assignments to avoid exhaustion and increase benefits to improve the well-being of teachers. Moreover, it is suggested that teachers in private schools must be provided with training and seminars, incentives, supplies for teaching, and other benefits that improve their productivity and become globally competitive educators.