Preparation method for concrete bricks

The invention provides a preparation method for concrete bricks. After the concrete bricks are formed in a die cavity by adopting a die structure consisting of an upper template, a lower template and a middle template positioned between the upper template and the lower template, the upper template enters the die cavity, and the solidified concrete is released from the middle template to realize mold release. The die can be installed in a machine tool or other frame to realize automatic or semi-automatic production, so that the production efficiency is remarkably improved and the manpower costcan be saved.