Agricultural geography is the interdisciplinary subject of agricultural science and geographical science, and agricultural geographical engineering is the further deepening and systematic application of the interdisciplinary research of geography and engineering in the field of modern agriculture and rural revitalization, and it is an important material basis to ensure the agricultural high-quality development. With the innovative development of modern agricultural science and technology and human-earth system science, the scientific and technological needs of regional agricultural infrastructure are increasingly strong, and agricultural geographical engineering experiments have become an important task of agricultural engineering technology research and farmland system management. This article expounds the scientific connotation, experimental principles and technical methods of agricultural geographical engineering, and takes the loess hilly and gully region as an example to carry out the experimental research on geographical engineering and discussed the countermeasures for high-quality agricultural development. Results show that: (1) Agricultural geographical engineering experiments mainly include soil and water allocation, soil layer composition, field experiment, ecological protection, geospatial analysis and monitoring for specific regional geographical environment and agricultural development issues, aiming to explore coupling law of resource elements for regional high-standard farmland construction and healthy agricultural ecosystem construction, and establish a sustainable land use system and multifunctional agricultural management model. (2) Agro-ecosystem experiments mainly includes trench slope protection methods, healthy farmland system structure, crop-soil matching relationship, economic analysis of farmland input and output, which aimed to reveals the coupling mechanism and optimal control approach of "crop-soil relationship" by carrying out interactive experiments and field trials for land improvement and crop optimization. (3) Optimization and regulation of crop-soil relationship is the main content of engineering experiment design, which includes six stages: climate-crop optimization, soil-body structure improvement, terrain-crop optimization, soil quality improvement, soil-crop optimization and benefit-crop optimization. (4) The core tasks of the application of agricultural geoengineering technology are to deepen the comprehensive research, reveal the micro-coupling mechanism and establish the engineering test paradigm, and its application path is mainly reflected in three dimensions of time, space, and logic. The geographical engineering experiment of modern agriculture and its application in the new era are conducive to enriching the frontier theories and methodology of agricultural geography, and are of great significance to the advancement of geographical engineering research and the decision-making of agricultural and rural high-quality development.