Surface structure of wadded seat and method of manufacturing surface structure of wadded seat

A method of manufacturing a surface structure of wadded seat which includes a trim cover having a plurality of trim cover pieces backed with wadding members and sewed together at ends, and covering a seat pad, and the method further including:

• a first step of forming first sewed portions, each by sewing two adjacent trim cover pieces at one end of each trim cover piece, while serving as seam allowance, the portions not backed with the wadding members;
• a second step of forming second sewed portions, each first by forming a continuous trim cover piece made of the sewed trim cover pieces, then by laying a long wadding member on the backs of the wadding members each provided on the backs of the continuous trim cover pieces, and finally by sewing, at both ends of the continuous trim cover piece, the trim cover pieces, the wadding members on the backs of the trim cover pieces and the long wadding member;
• a third step of forming third sewed portions, each by sewing, at both ends of each first sewed portion, the long wadding member to the end of each trim cover piece serving as seam allowance.