A system for recycling plastics, which enables a supply of recycled plastics having a stable quality required for the recycled products. A system for recycling a used plastic material as a resin material, which has (a) means for sorting used plastic materials by purpose of recycling, (b) means for crushing and melting said used plastic material sorted, (c) reviving means for regaining a desired property, and (d) means for measuring a physical property of a reclaimed plastic revived and indicating said measured physical property for quality assurance.