The purpose of this research is to determine student perceptions of the effects of project-based learning method on universal moral values in the Religious Culture and Moral Knowledge course taught in secondary school 7th grades. On the other hand, analysing students' perceptions according to demographic variables is among the aims of the research. The study group of the research conducted in the quasi-experimental model consisted of a total of 332 secondary school 7th grade students. In the study, which was designed as a pre-test-post-test control group, the data were obtained with the Information Form and the Universal Moral Values Scale. Descriptive statistical techniques were used in the analysis of the data. The results obtained as a result of the analyses are as follows: According to the participant students, the project-based learning method contributes to the development of general universal moral values and cognitive universal moral values at a low level, and to the behavioural universal moral values at a moderate level. However, the project-based learning method is not effective on the development of affective universal moral values. According to this situation in the research, it was evaluated that the religious culture and ethics course, which is taught with the support of the project-based learning method, provides support to the students in knowing and doing, while it is ineffective in the points of feeling, appreciating and internalizing. Possible reasons for this are listed as the students' new transition to the abstract operational period, the teacher's ability to use the method, and the relationship of this method with moral development. In the research, it has been proposed to develop new technology and practice-based methods that cover the cognitive, affective and behavioural dimensions of moral development, suitable for this age and current generation