Abstract: The treatment of black and odorous water bodies is a key component of the rural revitalization strategy, directly impacting the improvement of rural living environments and the advancement of ecological civilization. Establishing a scientific and precise cost index system for rural black and odorous water treatment projects not only provides crucial support for promoting comprehensive rural environmental management but also serves as an effective pathway for achieving refined project management. This paper briefly introduces the technical approaches for treating rural black and odorous water bodies and, based on this, breaks down cost indicators to establish a multi-level engineering cost index system. Through empirical analysis of typical projects with different treatment measures, the practicality and adaptability of this index system are verified. This index system not only provides accurate cost control references for project stakeholders but also holds significant theoretical and practical importance for enhancing multi-dimensional, full-lifecycle management of rural black and odorous water treatment projects.