A slide rail assembly, comprising: a first rail; a second rail movable relative to the first rail, the second rail comprising an engaging feature; and a driving mechanism comprising: a housing arranged on the first rail; a movable member movable relative to the housing; an actuating structure (42, 200) arranged on the movable member; and an elastic member configured to provide an elastic force to the movable member; wherein the actuating structure (42, 200) comprises a first part (62, 204) and a second part (64, 202) connected to the first part (62, 204); wherein the first part (62, 204) is configured to engage with the engaging feature of the second rail, and the second part (64, 202) is configured to prevent the engaging feature of the second rail from being disengaged from the first part (62, 204); wherein the housing comprises a longitudinal room, a longitudinal part, a bending part and a blocking wall, the longitudinal part is substantially parallel to the longitudinal room, the bending part is bent from the longitudinal part, the elastic member is arranged inside the longitudinal room, the movable member has a first side and a second side opposite to the first side, the first side is arranged with a first protrusion and a second protrusion, the actuating structure (42, 200) is arranged on the second side, the first protrusion abuts against the elastic member, the second protrusion is movable between the longitudinal part and the bending part, the blocking wall is configured to abut against the second protrusion when the movable member is located at a predetermined position, characterized by: an outline of the second part (64, 202) is wider than an outline of the first part (62, 204). a first rail; a second rail movable relative to the first rail, the second rail comprising an engaging feature; and a driving mechanism comprising: a housing arranged on the first rail; a movable member movable relative to the housing; an actuating structure (42, 200) arranged on the movable member; and an elastic member configured to provide an elastic force to the movable member; a housing arranged on the first rail; a movable member movable relative to the housing; an actuating structure (42, 200) arranged on the movable member; and an elastic member configured to provide an elastic force to the movable member; wherein the actuating structure (42, 200) comprises a first part (62, 204) and a second part (64, 202) connected to the first part (62, 204); wherein the first part (62, 204) is configured to engage with the engaging feature of the second rail, and the second part (64, 202) is configured to prevent the engaging feature of the second rail from being disengaged from the first part (62, 204); wherein the housing comprises a longitudinal room, a longitudinal part, a bending part and a blocking wall, the longitudinal part is substantially parallel to the longitudinal room, the bending part is bent from the longitudinal part, the elastic member is arranged inside the longitudinal room, the movable member has a first side and a second side opposite to the first side, the first side is arranged with a first protrusion and a second protrusion, the actuating structure (42, 200) is arranged on the second side, the first protrusion abuts against the elastic member, the second protrusion is movable between the longitudinal part and the bending part, the blocking wall is configured to abut against the second protrusion when the movable member is located at a predetermined position, characterized by: an outline of the second part (64, 202) is wider than an outline of the first part (62, 204).