Determining secondary school students' emotional and psychological well-being and understanding the factors affecting these constructs is important due to the increasing interest in educational psychology. The study group consisted of 254 middle school students aged 10-14. Hierarchical regression analysis was used to determine the level of prediction of emotional and psychological well-being of middle school students by age and career development. In the first block of the analysis, age, and average academic achievement were taken, and it was determined that they explained 10% of the variance in emotional and psychological well-being. In the second block, career development sub-dimensions were taken, and it was seen that these sub-dimensions contributed 24% to emotional and psychological well-being. The findings obtained from the study were discussed in comparison with the studies in the literature, and suggestions were made for field workers.