Gray scale image analysis was applied to evaluate visual textures of 11 kinds of knitted fabric patterns. The angular second moment, contrast, correlation and entropy extracted from the gray level co-occurrence matrix were measured as textural feature parameters. The fractal dimension was determined from the fractal analysis of the relief of the curved surface of the gray level image. Complexity and fineness of textural patterns of knitted fabrics were subjectively evaluated according to the rating scale method, and the relationship between their sensory evaluation values and the textural feature parameters containing the fractal dimension was examined. The entropy, angular second moment and contrast have a good correlation with complexity, and the fractal dimension has a high correlation with fineness. Surface appearance and visual textures of knitted fabric patterns were discussed in terms of uniformity, directionality, local variation, information quantity, complexity and fineness, corresponding to human visual perception. We proposed that these visual feature parameters are useful for the appearance evaluation of textures and textile design.