Reed mark and yarn interval irregularity of woven fabric were studied using image analysis and Fourier transform. The fabric surface intensity data were collected from transmitted light through fabrics using line sensor camera. The results were compared with human inspection results. The peak at reed space grew higher as the fabric was evaluated as lower quality. The CV(%) and power spectra of yarn interval did not show the relationship to the fabric surface quality. However the half value width of the peak at yarn interval was changed along the fabric visual quality. The research results can be extended to on-line monitoring of the fabric surface quality.