The invention provides an outdoor directional sound advertising device which is suitable for outdoor installation, and capable of sending sound advertising directionally in a certain region and producing no noise pollution to other regions outside the specific region. The invention can be used in outdoor public places to improve advertising effects. The device provided by the invention comprises adevice for generating ultrasonic wave sound directionally and a shell, the shell has an opening on one side which is used as exit of directional sound, the opening of the shell is provided with a nylon mesh pad, further, a humidity is arranged outside of the shell, a waterproof rolling screen is arranged outside the nylon mesh pad, and a control unit is provided to connect with the humidity sensor and power mechanism of the waterproof rolling shutter, the control unit controls rolling or unfolling of the waterproof rolling shutter according to the humidity; further, a human infrared detectoris also included, when exist of a people is detected, a sound source device is controlled to open or close advertising sound signal and wave carrying signal. The invention can also save resources effectively on the base of meeting the need of outdoor waterproof and dustproof.