Abstract: A rotating shaft assembly and an electronic device, where the rotating shaft assembly includes a panel and a rotatable support mechanism. The rotatable support mechanism includes a swing arm, a fixed structure, a limit part, and a support structure. The support structure is provided with a mounting plane, and the panel is fastened to the mounting plane; a first limit portion is formed on the swing arm; and the limit part is connected to the support structure, and a second limit portion is formed on the limit part. When the screen is in a folded state, the limit part is separated from the swing arm. When the screen is in an unfolded state, the second limit portion of the limit part can abut against the first limit portion of the swing arm, thereby implementing mutual constraint between the swing arm and the support structure.