Recently, it is one of a major problem in automotive industry that wrinkles on seat interior occur at detaching between seat covering and padding material. To laminate seat trim cover and padding material is applied to thermoplastic composite material such as Web Hot Melt. Flame lamination is also using for seat trim cover and padding material lamination but it can be only applied on polyurethane padding and makes toxic substance. The purpose of this research verifies and suggests the way to improve seat appearance and heat resistance using polyurethane reactive (PUR) material of thermosetting plastic. Viscosity and melting temperature can be adjusted coating amount on padding material unlike traditional method to coat leather. We develop PUR that works on thin film at padding material and find optimum situation (method and amount) for seat trim cover and padding material. PUR is cross-linked by moisture concentration in the air and pressure. It keeps lamination state at high temperature such as serve environment. Also we advance an additional jig to match seat trim cover and padding material by low tacky characteristic of PUR. This jig can increase productivity in seat manufacturing process.