The invention relates to a sound and heat insulation composition, inorganic powder is added with EVA (ethyleno vinyl acetale copolymetr), plastic and a crosslinking agent, and by reasonable ratio and combined effect of the EVA, the plastic and the crosslinking agent, the inorganic powder can full play sound and heat insulation performances, so that the prepared sound and heat insulation composition can not only keep good sound and heat insulation performances for a long time, but also has appropriate softness and hardness, and can achieve close fitting with car body interior uneven parts; the sound and heat insulation composition has good sound and heat insulation performances, can keep for a long time, and has appropriate softness and hardness, so that when the sound and heat insulation composition is composited together with soft polyurethane foam for using as a heat insulating layer material of a car front wall, the assembly construction is easy, close fitting with car body interior can be realized, and the implementation of effective sound insulation and noise reduction of the car cabin interior and long-term use can be further ensured.