Color is frequently used in urban outdoor spaces, but little research has studied its psychological effects. This study explores the influence of sidewalk floor color on the restorative walking experience in a busy, inner city street lacking natural greenery. We used an achromatic street view image with no vegetation or trees as control. Red, green, and blue were used as “artificial” intervention colors in the sidewalk ground plane to generate 3 visual stimuli. Participants (n=66) rated the perceived restorativeness of the scene and their subjective mood on viewing each image via an online survey. The results indicate “artificial” green ground color, e.g. provided by paint or colored material, promoted a more restorative walking experience enhancing hedonic tone and arousal and increased relaxation more than red ground color. All three color-interventions improved perceived restorativeness and arousal. This study advances the understanding of the psychological impact of color in urban design.