This study investigated the mechanical properties and forming characteristics of flanged parts made of AZ61 magnesium alloys via hot working. The bearing cover of the gearbox in cars was selected as a carrier in hot forging to probe into the formability of magnesium alloys. A high-speed metal test machine was used for compression tests under different forming temperatures and strain rates to obtain stress-strain curves. The stress-strain data are applied to the Finite Element Method to analyze the formability of the bearing cover. Finally, based on the comparison of simulation and experimental results, we conclude that under the same billet heating temperature and low strain rate, the forming load was small and no cracks developed on the flanges of forged parts. However, under the same condition, the microstructure of the part was coarse. This study also attempted to identify a method for manufacturing a bearing cover with a low forging load, and determined how temperature influences hardness and microstructure of the bearing cover.