The invention discloses an assembly type ballastless track system. The assembly type ballastless track system comprises steel rails, fastening systems, an assembly type track slab, a packing layer anda lower foundation. The assembly type track slab comprises multiple unit plates and connecting mechanisms connecting the unit plates, wherein at least two connected unit plates are arranged in the transverse direction of the assembly type track slab, and at least two connected unit plates are arranged in the longitudinal direction of the assembly type track slab. The assembly type track slab is adopted, the large-size and large-weight ballastless track slab is divided into pieces, the factory prefabrication difficulty is reduced, the assembled track slab is small in deformation, transport andlifting are convenient, the replacement and maintenance difficulty is greatly reduced, and the adjusting capacity and the repairing capacity of the track system are enhanced; and an existing base isremoved, the concrete pouring workload on the site is reduced, the use amount of building materials is reduced, meanwhile, the construction speed and the construction efficiency are improved, and whenthe space height is limited, the occupied height of the track system can be reduced as well.