The invention provides a fly ash stabilization automatic control method and system. The fly ash stabilization automatic control system comprises a switch function block, a sequence control function block, a valve function block, a motor function block, an analog quantity function block and a controller function block. The function blocks are combined for performance and used for fly ash conveying control, solid drug conveying control, liquid drug equipping control, fly ash weighing and delivery control, drug weighing and delivery control, stirrer control, granulation control and finished product conveying control. According to the fly ash stabilization automatic control method and system, the fly ash stabilization process can be automatically controlled so that reliability is high and anti-interference performance is great.