Over the past century,the scientific foundation of embryonic development has primarily relied upon meticulous examination of developmental processes in model organisms.However,investigating the development of mammals has presented numerous challenges,including interspecies disparities,ethical considerations,and technical constraints.With the rapid advancement of stem cell technology,researchers have endeavored to overcome these obstacles by harnessing the potential of stem cells to generate sophisticated in vitro embryo models.The rapid advancement of stem cell technology has revolutionized our approach to study embryonic development.While the ability of current embryo models to fully simulate the authentic developmental process is yet to be verified,they undeniably present new possibilities for developmental biology research.This review primarily focuses on mouse and human,summarizing the types of stem cells used in constructing embryo models and elucidating the roles and importance of different stem cells in simulating developmental processes.This review systematically presents and dissects crucial events and spatiotemporal dynamics in the embryonic development of both mice and humans across various stages.We thoroughly discuss the remarkable milestones achieved by existing embryo models,explore methods for evaluating the biomimicry of these models,and highlight the crucial role of bioengineering methods in embryo model development.The pivotal role of bioengineering in advancing embryonic model development is underscored,emphasizing its indispensable contribution to providing the requisite technical scaffolding for the realization of instruct multicellular induced self-organization with high-level spatiotemporal orders.Additionally,we provide perspectives for the optimization and progressive refinement of embryo models,so as to improve their relevance and applicability.In summary,engineered advances in stem cell-based synthetic development could not only improve our understanding of the inherent complexities of embryos,but also hold the potential for applications in disease research,drug screening,reproductive medicine,toxicological assessments,and other related fields,thereby opening new avenues for both fundamental and translational research.