A slide rail assembly, comprising: a first rail; a second rail movable relative to the first rail; a third rail movably mounted between the first rail and the second rail; and a damping device mounted to the first rail; wherein the third rail comprises a first pushing feature and a second pushing feature respectively located at two sides of the damping device; wherein during a process of the third rail being moved relative to the first rail along an opening direction, the third rail is configured to push the damping device through the first pushing feature to allow the damping device to provide damping effect; wherein during a process of the third rail being moved relative to the first rail along a retracted direction, the third rail is configured to push the damping device through the second pushing feature to allow the damping device to provide damping effect; characterized by: a contact member mounted to the first rail, and a synchronization member movably mounted to the third rail, wherein when the second rail is moved from a retracted position along the opening direction, the third rail is synchronously moved with the second rail relative to the first rail along the opening direction through the synchronization member; and when the second rail and the third rail are moved to a first predetermined position, the third rail is no longer synchronously moved with the second rail due to interaction between the synchronization member and the contact member; and a blocking structure and a locking member, wherein the blocking structure is mounted to the first rail, and the locking member is configured to abut against the blocking structure, in order to prevent the second rail from being moved relative to the first rail from the retracted position along the opening direction, the locking member is pivoted to the second rail. a first rail; a second rail movable relative to the first rail; a third rail movably mounted between the first rail and the second rail; and a damping device mounted to the first rail; wherein the third rail comprises a first pushing feature and a second pushing feature respectively located at two sides of the damping device; wherein during a process of the third rail being moved relative to the first rail along an opening direction, the third rail is configured to push the damping device through the first pushing feature to allow the damping device to provide damping effect; wherein during a process of the third rail being moved relative to the first rail along a retracted direction, the third rail is configured to push the damping device through the second pushing feature to allow the damping device to provide damping effect; characterized by: a contact member mounted to the first rail, and a synchronization member movably mounted to the third rail, wherein when the second rail is moved from a retracted position along the opening direction, the third rail is synchronously moved with the second rail relative to the first rail along the opening direction through the synchronization member; and when the second rail and the third rail are moved to a first predetermined position, the third rail is no longer synchronously moved with the second rail due to interaction between the synchronization member and the contact member; and a blocking structure and a locking member, wherein the blocking structure is mounted to the first rail, and the locking member is configured to abut against the blocking structure, in order to prevent the second rail from being moved relative to the first rail from the retracted position along the opening direction, the locking member is pivoted to the second rail. a contact member mounted to the first rail, and a synchronization member movably mounted to the third rail, wherein when the second rail is moved from a retracted position along the opening direction, the third rail is synchronously moved with the second rail relative to the first rail along the opening direction through the synchronization member; and when the second rail and the third rail are moved to a first predetermined position, the third rail is no longer synchronously moved with the second rail due to interaction between the synchronization member and the contact member; and a blocking structure and a locking member, wherein the blocking structure is mounted to the first rail, and the locking member is configured to abut against the blocking structure, in order to prevent the second rail from being moved relative to the first rail from the retracted position along the opening direction, the locking member is pivoted to the second rail.