A child seat includes a main support frame, a swing frame connected pivotally to the main support frame, a seat frame connected to the swing frame and convertible between a high chair configuration and a swing configuration, a first locking mechanism including a latch disposed movably between the swing frame and the main support frame and engaged releasably with the main support frame, and a second locking mechanism including a protrusion provided on the swing frame and movable between a first position, where movement of the latch is prevented, and a second position, where movement of the latch is permitted so that the latch can move away from the main support frame, thereby converting the seat frame to the swing configuration.