This study investigates the mediating effect of students Emotional Stability on the relationship between Perceived Learning Stress and Mathematics Performance among senior high school students in Don Marcelino District during the school year 2022-2023. The research employs a descriptive-correlation research design, utilizing a quantitative approach through the administration of a survey questionnaire. The result showed that a big percentage of the respondents display moderate levels of Emotional Stability, moderate levels of Perceived Learning Stress, and an approaching proficiency level in Mathematics Performance. Furthermore, the study revealed a negative correlation between perceived learning stress and emotional stability, and between perceived learning stress and mathematics performance. However, the research findings indicated that there is a positive correlation between the students levels of emotional stability and mathematics performance. Finally, the study identified a significant mediation effect of students emotional stability on the relationship between perceived learning stress and mathematics performance. These results addressed the research objective, highlighting the importance of emotional stability as a mediating factor in the relationship between students perceived learning stress and mathematics performance. It sheds light on the complex interplay between the variables, emphasizing the need for interventions and support systems that promote emotional well-being to enhance academic outcomes.