A zoom lens barrel assembly includes: a zoom ring having a cylindrical shape, and comprising an inlet portion formed in a boundary of one end thereof and a first protrusion; a guide ring disposed around the zoom ring, and comprising a first guide hole through which the first protrusion passes, and movably supporting the zoom ring in an axial direction, and a second guide hole; and a cylinder disposed in the zoom ring, for moving and rotating between a position where the cylinder is accommodated in the zoom ring and a position where the cylinder moves away from the zoom ring in the axial direction, and comprising a second protrusion that passes through the second guide hole, accommodated in the inlet portion at the position where the cylinder is accommodated, and pressing one end of the inlet portion when the cylinder moves away from the zoom ring.