Disclosed is a laundry treatment apparatus equipped with an exhaust type drying system, which is capable of not only enhancing drying efficiency while reducing consumption of energy and cooling water required to dry laundry, but also achieving smooth exhaust of air even when a water trap is formed in a drainage duct. The laundry treatment apparatus includes a casing, an outer tub, an inner tub, a drainage duct for guiding wash water stored in the outer tub to be discharged to the outside of the casing, a first exhaust duct connected, at one end thereof, to the drainage duct, to guide air present in the outer tub into the drainage duct, and a second exhaust duct upwardly branched from the drainage duct, to exhaust air present in the drainage duct to the outside of the outer tub or the outside of the cashing.