Improving the quality of teaching natural science for grade 6 pupils, according to the 2018 General Education Program at secondary schools, is mandatory. Management activities are necessary to improve the quality of teaching. The tasks and purposes of this study are to analyze and evaluate the current status of management activities, find out the limitations and causes of the limitations, thereby proposing management measures to improve the quality of teaching Natural Science in grade 6 according to the 2018 General Education Program at secondary schools in Bien Hoa city, Dong Nai province. This study conducted a survey of 114 people including 20 board of directors, management staff, and 94 teachers of secondary schools according to the following contents: (i) Survey on awareness; (ii) Survey on planning; (iii) Survey on organizing teaching activities; (iv) Survey on directing teaching activities; (v) Survey on testing and evaluating teaching activities. The survey, combined with qualitative research, helps to correctly assess the current situation, limitations, and causes of limitations, which is the basis for perfecting management measures to improve the quality of teaching Natural Sciences for grade 6 according to the 2018 General Education Program at secondary schools, thereby contributing to the comprehensive development of educational quality and pupil capacity in Bien Hoa city, Dong Nai province.