Abstract: An adsorption positioning device suitable for installation on a cutting machine, which is suitable for cutting a material unit, includes a platform and two platen units. The platform includes a table for supporting the material unit, and a plurality of air holes extending through the table. The platen units are disposed on the table. The table and each platen unit are configured for cooperating with a lateral side of the material unit to define a channel that communicates with corresponding ones of air holes. The channel and the air holes are suitable for causing the material unit to be adsorbed on the table under a negative pressure state.