A key support structure of a keyboard device includes a first member and a second member that supports the first member. The first member is pivotal about a first axis that extends in a first direction and movable with a degree of freedom of movement in a rolling direction, which is a direction of rotation around a second axis extending in a second direction that is substantially orthogonal to the first direction. the second member restricts a movement of the first member in the first direction, while pivotally supporting the first member about the first axis.