Today, in accordance with emphasizing the importance of character education, science educators have tried to implement character education in the field of science education. Therefore, this research aims to confirm the possibility of the realization of 'Practice Centered Mechanism of Manifesting Character' developed on the basis of character education theory through the application of the NABI Program based on Nature-Study. For this, the NABI program was applied to 24 3rd grade students of an elementary school for a period of ten months. Qualitative data was collected like students' reports, journals, and video recording of the classes. This data was classified into 'value, judgment, action,' the steps of 'Practice Centered Mechanism of Manifesting Character,' and text was written by interpreting the data. The research resulted in the following: First, students formed 'value' by making a connection with the objects. And the various values -individual, interpersonal, social, ecological, and spiritual -are formed according to the type of objects with which the students felt a connection to. Second, students need to judge the problems of the real world at the 'judgment' step. Third, at the 'action' step, students practice moral behavior in relation to the sympathy or feeling they felt with the objects that they made a connection to. In conclusion, 'Practice Centered Mechanism of Manifesting Character' can be realized through the application of the NABI Program. The NABI Program can be a definite way to implement character education in the field of science education.