A keyswitch structure includes a base plate, a keycap, and a keycap support mechanism that supports the keycap above the base plate in a vertical direction. The keycap and the keycap support mechanism extend lengthwise in a lengthwise direction. The keycap support mechanism includes an outer support and an inner support pivotally connected to each other. The outer support surrounds the inner support. The inner support includes a support body and a reinforcement part. The reinforcement part is embedded in the support body. The reinforcement part is greater in elastic modulus than the support body. The inner support defines a side connection section on both sides of the inner support in the lengthwise direction. Each side connection section includes at least one base plate connecting portion and at least one keycap connecting portion. The reinforcement part extends into the two side connection sections.