The invention discloses a control method of a soft porcelain forming device. The control method comprises the following steps: at first, controlling an air cylinder to work to enable a clamping frameto clamp a support rod, then, controlling the air cylinder to work to enable the air cylinder to drive the support rod to move above a module along a groove, controlling a first electromagnet and a second electromagnet to be electrified to enable the first electromagnet and the second electromagnet to attract each other, controlling the air cylinder to drive the air cylinder to return, controllingan air claw to work to enable the clamping frame to loosen the support rod, controlling a first motor to work to enable the support rod to drive the module to move downwards to extrude soft porcelainplaced on a conveyer belt, controlling the first motor to drive the module to return, and at the moment, forming a pattern on the surface of the porcelain; and when module changing is needed, controlling a first circular plate to rotate in the circumferential direction of the support rod, and when the groove is above the module once more, controlling the first circular plate to stop rotation. Thecontrol method is high in working efficiency and degree of automation and wide in range of application.