Bismuth telluride‐based devices are capable of converting low‐quality thermal energy into electrical power via the Seebeck effect. This transformative process not only extends the spectrum of energy utilization but also significantly amplifies energy efficiency. This review serves as a comprehensive guide, elucidating the intricate design considerations essential for optimizing bismuth telluride‐based devices in both electrical and structural design. By exploring various application scenarios, it identifies critical parameters crucial for device effectiveness. Furthermore, the current landscape of thermoelectric (TE) devices is meticulously analyzed, synthesizing their developmental trajectory and contrasting it with stringent design requirements. Through this comprehensive analysis, it pinpoints key challenges that impede the maximal performance of existing TE devices. Envisioning the trajectory of bismuth telluride‐based TE materials, this review makes projections regarding their future application trends. Traversing through contemporary mechanisms and technologies, it offers practical solutions and potential avenues aimed at enhancing the efficiency of TE devices. Ultimately, this discourse endeavors to provide invaluable insights, furnishing a roadmap for the advancement and refinement of TE devices in the years ahead. By proposing feasible solutions and charting plausible directions, it aspires to stimulate innovation and drive transformative progress in the domain of TE materials and science.