A bike rack includes two main arms, two links, and a locking mechanism. The locking mechanism includes a first pivot member pivotally mounted on a first main arm, a second pivot member pivotally mounted on a second main arm and pivotally connected with the first pivot member, and a control handle secured to the second pivot member to drive the locking mechanism to expand and fold the two main arms. Thus, the control handle is held by a user' one hand to operate the locking mechanism so as to lock and unlock the bike rack, thereby facilitating the user mounting and detaching the bike rack.