The invention discloses a connecting-rod variable-frequency spraying machine, comprising a machine seat, wherein one end of the machine seat is provided with a machine body through a transverse motor; a spray nozzle component and a spray nozzle are installed on the machine body through a drag chain; a worm speed reducer and a gear reducer motor are installed on the machine body; a connecting rod arm is installed between each of the worm speed reducer and the gear reducer motor and the drag chain; an air control box connected with the worm speed reducer and the gear reducer motor is installed on the machine body; a paint inlet communicated with the spray nozzle is installed in the machine body; the tail end of the drag chain is provided with a moving-die electromagnetic valve, a fixed-die electromagnetic valve and a blowing electromagnetic valve; a power line and an optoelectronic switch are installed on the machine body; the bottom part of the machine seat is provided with an installation seat; an air inlet pressure regulating valve is installed on the paint inlet; a spray nozzle angle regulating switch is installed between the spray nozzle component and the spray nozzle. The connecting-rod variable-frequency spraying machine has the beneficial effects of being practical, being low in production cost, facilitating the spraying painting of a product, realizing the automation of spraying painting and improving the working efficiency of spraying painting.