The present invention provides a flaskless molding machine that can use a matching plate of different thicknesses. The flaskless molding machine has two molding flasks that have a matching plate sandwiched between them, the two molding flasks being positioned in a way such that one of opening ends of the molding flasks is opposed to each other and each of the other opening ends of the molding flasks is engaged with a squeezing board, and a pair of spaces is formed, into which spaces molding sand is filled by air through each of the openings for introducing the molding sand, disposed on a wall of each of the two molding flasks that are opposed to each other, the flaskless molding machine thus constituted being able to mold two molds by squeezing the molding sand with the squeezing boards.