This study aims to explore the impact of guidance/counseling by teachers on students' moral development in class VIII-1 of SMP Negeri 2 Sei Bamban. The population studied consists of 32 students from class VIII-1. Data collection methods utilize Likert model questionnaires, employed to measure individuals' or groups' attitudes, opinions, and perceptions towards social phenomena. Data analysis involves four stages: (a) planning, (b) action implementation, (c) evaluation, and (d) reflection. The analysis results indicate a significant improvement in the average scores of guidance/counseling questionnaires from cycle I to cycle III. The average scores increased from 3.20 in cycle I to 3.41 in cycle II and reached 3.56 in cycle III. Additionally, the correlation between teacher guidance/counseling and students' moral development also increased from cycle I to cycle III. The correlation increased from 73.9% in cycle I to 74.3% in cycle II and reached 86.5% in cycle III.