As an emerging interdisciplinary field, rural designology is an important part of building the knowledge system of independent design in China. This article takes the construction of the theoretical system of contemporary Chinese designology that the author has continuously explored over more than twenty years (2004-2026) as its academic background, and uses the "Design-world" as its logical basis to systematically elaborate on the core theoretical issues of rural designology. The article delves into the research object of rural designology—whole-life design, and clarifies its core principles of "benefiting people from nature", worldview and methodology "systems thinking", epistemology "opening theory", and outcomes theory "theory of knowledge and action to achieve success". On this basis, the article constructs six core structural systems for rural designology—Production Designology, Life Designology, Ecological Designology, Cultural Designology, Social Designology, and Educational Designology—and explores their future development paths. The study believes that the rural designology system is a comprehensive design theoretical framework based on the concept of whole-life design and fundamentally based on the principle of "benefiting people from nature". This system is fundamentally based on agricultural design, with industrial design, digital intelligent design, and service design as tools, integrating the three major designology subsystems of rural production, living, and ecology (i.e., the "integration of three rural aspects"), and exhibits a holographic structural feature. Its essence is a future-oriented designology system, which holds significant theoretical value and practical significance for promoting comprehensive rural revitalization and achieving urban-rural integrated development.