The invention discloses a solid-liquid phase continuous compounding device for stainless steel compound plate slabs. By adopting the device, stainless steel compound plate slabs can be produced continuously with high efficiency, low cost and high quality. The solid-liquid phase continuous compounding device for stainless steel compound plate slabs comprises two uncoilers, two wire brushes, guide rollers, casting systems, protective atmosphere heating systems, crawler-type crystallizers and cooling separation systems; the two uncoilers are arranged in the feeding position in a mutually staggered manner; the two wire brushes are arranged behind the uncoilers; the guide rollers are arranged behind the wire brushes; the protective atmosphere heating systems are arranged below the guide rollers; the casting systems are arranged on two sides of the protective atmosphere heating systems; the crawler-type crystallizers are arranged below the casting systems; and the cooling separation systemsare arranged at the bottom. By adopting the device, not only are thin plate slabs of single metal material can be produced, but also compound thin plate slabs of different metal materials can be produced continuously; and the device is particularly suitable for continuous production of stainless steel composite plate slabs.