The invention relates to a software implementation method for a CRTSIII type ballastless track layout design. A CRTSIII type ballastless track plate system belongs to a novel ballastless track technology, and an appropriate method and software for performing layout design are unavailable in ballastless track layout construction. The method comprises the following steps: establishing a line foundation database; determining a main template design and a standard simply supported beam layout scheme; designing a simply supported beam section layout; finishing subgrade and tunnel section layout design according to a determined major plate type track plate length and slab joint; establishing a compensating plate database and designing a deformed plate scheme in reference to the factors of the length of a deformed plate and a fastener distance. A track plate distribution calculation general model and an algorithm adapting to different structural types of subgrades, bridges and tunnels are established, so that track plate distribution calculation in a fixed line section is realized, automation of layout design is realized, and the working efficiency is increased.