Abstract: The rock and soil layer serves as the fundamental basis of ecosystems. Open-pit coal mining causes the complete destruction of the original overlying geotechnical system, leading to severe environmental consequences. The ecological restoration of open-pit coal mining usually results brand new rock and soil layers with a artificial reconstruction process. The reconstruction of rock and soil layer is pivotal for restoring and enhancing mine ecosystem functions. It aims to elucidate the evolutionary process of rock and soil layer reconstruction across different development stages, innovate the principles and methodologies of reconstruction, and explore adaptive reconstruction technologies for critical layers within reconstructed geotechnical profiles. The ultimate goal is to provide fundamental theories and key technical support for ecological restoration in open-pit coal mines. It systematically reviews the impacts of open-pit mining on the original geotechnical system (strata) and its environmental consequences. It clarifies the interrelationships among geotechnical layer and soil reconstruction, the critical zone, and Earth system processes. The concept and connotation of rock and soil layer reconstruction are defined, emphasizing that the reconstruction process entails restoring the functional integrity of the entire geotechnical system, including both soil and rock layers. The study asserts that broadly defined soil reconstruction aligns with rock and soil layer reconstruction, whereas narrowly defined soil reconstruction focuses solely on the soil layer. The development of rock and soil layer reconstruction in open-pit coal mines is categorized into four evolutionary stages. The study delineates the background, characteristics, and research foci of each stage, from Rock and Soil Layer Reconstruction 1.0 to 4.0, illustrating the progressive enhancement of geotechnical functionality cognition and continuous advancement in mine rehabilitation technologies. A crucial finding is that the economic investment in mine soil amelioration and reconstruction projects exhibits a significant inverse correlation. The Ecological Niche Principle involves quantitative analysis of stratified ecological niche characteristics, particularly ecological niche suitability and competitive overlap, to determine the spatial configuration and hierarchical relationships of reconstructed layers. This principle addresses key questions such as whether to merge layers, the optimal number of layers, and their spatial relationships, ultimately guiding the formation of the fundamental profile configuration. The Critical Layer Reconstruction Principle focuses on identifying and enhancing key functional layers through ecological function analysis and optimization measures. This principle aims to achieve optimal critical layer functionality and the best possible rock and soil profile configuration. Applying these principles and methodologies, the study presents a case of ecological restoration in an open-pit coal mine in the eastern grassland region of China, demonstrating the development and application of adaptive critical layer reconstruction technologies tailored to specific geological and climatic conditions. The research provides detailed optimization strategies for reconstructed profile configurations and specific methods for topsoil critical layer reconstruction, achieving significant practical outcomes.