The invention provides a lower cushion layer for a road bed slab and a vibration reduction track and belongs to noise reduction equipment for track traffic. The lower cushion layer for the road bed slab is used for being mounted on the lower portion of the road bed slab and comprises a plurality of stacked wave resistance layers, a first surface and a second surface. Each wave resistance layer comprises a plurality of fixedly-connected wave resistance units; each wave resistance unit comprises a base body; the base bodies are box bodies and are internally provided with scattering bodies, and wrapping layers for fixing the scattering bodies are arranged between the base bodies and the scattering bodies; the first surface gets close to or away from the road bed slab, and the second surface is opposite to the first surface; each base body comprises an opening; and all the openings of the wave resistance units of the lower cushion layer for the road bed slab face the first surface. Through the lower cushion layer for the road bed slab, vibration of track traffic can be effectively reduced, and the lower cushion layer for the road bed slab is used in the vibration reduction track so that vibration transmission of the vibration reduction track can be reduced.