Permanent adaptation and readjustment, as an essential condition of performance in education, requires the development of self-assessment skills in both students and teachers. Self-evaluation completes the evaluation process and refines it by evaluating one's own merits, establishing the value of one's activity. The study on the dimension and method of self-analysis regarding the teaching activity supported by teachers in pre-university education showed a strong consistency between the results of external evaluation and self-evaluation, awareness of the importance, usefulness and necessity of the selfevaluation process in supporting / achieving professional performance. The importance of the selfassessment process lies in deepening self-knowledge and developing self-awareness. At the same time, the self-assessment process allows the identification of the weak aspects of one's own activity, their causes, possible solutions for the improvement of those aspects. Moreover, with regard to the tool frequently used in the self-assessment process by pre-university teachers, the evaluation sheet is noted, which is drawn up on the basis of performance indicators established by a higher hierarchy rather than a reflective journal, indicating the dependence on external perception, the need for external validation of one's own performance.