The invention provides a solid carbon dioxide former and a control method thereof,and further relates to the technical field of production of solid carbon dioxide. The solid carbon dioxide former comprises a squeeze-type cavity,a compression component,a material storage tower and a die head component. The compression component comprises a first power device,a piston connection rod and a piston,wherein the first power device,the piston connection rod and the piston are connected in sequence; the piston is arranged in the squeeze-type cavity,and the first power device drives the piston connection rod to move back and forth in the horizontal direction to drive the piston to move back and forth in the squeeze-type cavity so that granular solid carbon dioxide can be squeezed into blocky solid carbon dioxide. The material storage tower is vertically arranged above the squeeze-type cavity and communicated with the squeeze-type cavity,and is used for adding the snowflake-shaped carbon dioxideto the squeeze-type cavity. The material storage tower is adopted for feeding,and the process is omitted that physical changes of liquid carbon dioxide occur in a cavity and the liquid carbon dioxideis changed into the snowflake-shaped carbon dioxide,so that working time is saved,and the squeeze working efficiency is greatly improved.