An automatic spray gun includes a cylinder for disposing a motor and a turbine therein and sealed by a sealing cap and an outer cap, a sleeve perpendicularly integrated with lower periphery of the cylinder, a container cap integrated with an under side of the sleeve for covering a paint container, a Y-shaped pressing means suspended from an axial rod on a top of the sleeve, a nozzle with a group of fittings engaged in the sleeve, a fist half handle integrated to the bottom of the cylinder and combined with a second half handle by screws, a tube, a hair switch and a number of electric wires disposed in the handle for connection of electric power to the motor through the switch which controls the rotation of the motor.