This study was carried out in order to obtain the quantitative analysis of the seam puckering to the course direction of plain-weft knit fabrics using moire topography. which enables us to find the way to evaluate seam puckering more systematically. The experimental results are as follow: 1. The total puckering value of plain weft knit fabrics increases with values of cover factor. 2. The total puckering value of plain weft kint fabrics with same cover factor increases with values of yarn number. 3. Though the distance change from the seam line to the measured line, the tendency of puckering value, using with same yarn number and same cover factor, is not altered.