A lock unit used for an electronic apparatus that includes a foldable and unfoldable housing that has a first surface that is foldable, and a second surface orthogonal to the first surface includes a lock member that locks the housing in a folded state, an operation member that moves the lock member and releases a lock of the housing by the lock member, and a transmission mechanism that transmits a driving force applied to the operation member to the lock member by changing an operating direction of the operation member to another direction, and moves the lock member in the other direction, wherein the operation member is provided on the second surface, and an operating direction of the operation member is a first direction perpendicular to the second surface, the lock member projecting in a second direction orthogonal to the first surface, and a moving direction of the lock member being a third direction orthogonal to the first and second directions.