Abstract: A circular knitting machine structure comprises knitting needles and sinkers. Each knitting needle is controlled to move on a first half knitting track or a second half knitting track. A retracting time point of the first half knitting track is later than that of the second half knitting track. One side of the sinker facing the knitting needle is formed with an inclined plane. When the knitting needle is used for knitting, a surface yarn and a bottom yarn are fed therein. When the knitting needle moves on the first half knitting track, a standard plating is knitted without changing the position of the surface yarn. When the knitting needle moves on the second half knitting track, the surface yarn leans against the inclined plane of the sinker transitorily, the position of the surface yarn is changed relatively to the bottom yarn, and an interchanged plating is knitted.