The invention relates to a sanding belt special for a metal composite plate and a preparation method thereof. The sanding belt consists of a grinding material layer, an anti-clogging layer, a composite glue layer, a bottom glue layer, a basic glue layer, a matrix processing layer, a matrix layer and a matrix anti-static layer. The preparation method comprises the following steps of: coating the matrix processing layer and the matrix anti-static layer on two cloth-based faces by a knife coating method; coating the basic glue layer and the bottom glue layer on the matrix processing layer sequentially; implanting ground sand into the bottom glue layer; and coating the composite glue layer and the anti-clogging layer on the bottom glue layer sequentially, wherein the part, which is exposed from the anti-clogging layer, of the ground sand implanted into the bottom glue layer forms the grinding material layer; the matrix processing layer is prepared from phenolic resin and butadiene styrene latex; the matrix anti-static layer is prepared from chlorobutyronitrile latex and an anti-static agent; the basic glue layer is the common phenolic glue; the bottom glue layer and the composite glue layer are prepared from water-soluble phenolic resin, heavy calcium sulphate and the like; and the anti-clogging layer is prepared from amino ester, potassium fluoborate and the like. When the sanding belt is used, the anti-clogging layer falls off continuously and the grinding material layer falls off to take away heat and chips which are generated during grinding continuously, so that the sanding belt has grinding and polishing action.