Magnesium‐based thin‐film bioelectronics are a promising platform for transient, biocompatible, and bioresorbable devices addressing the challenges of temporary biomedical applications. Magnesium's unique properties, including biodegradability, biocompatibility, and suitability for miniaturized electronics, make it ideal for short‐term diagnostic and therapeutic interventions. This review explores recent advances in magnesium thin‐film bioelectronics, focusing on fabrication techniques, performance optimization, and integration into multi‐functional systems. Key challenges such as controlled degradation, mechanical flexibility, and reliable electrical performance are discussed alongside figures of merit like stability and bioresorption kinetics. Applications include temporary neural interfaces, biodegradable sensors, transient drug delivery systems, and bioresorbable stimulatory platforms. Finally, we highlight opportunities for magnesium‐based devices in personalized medicine and minimally invasive healthcare, while addressing the barriers to transitioning from prototypes to scalable commercial solutions.