To establish valid indexes for streetscape visual evaluation, this paper proposed 6 quantitative indexes to refl ect objective visual properties of streetscapes based on the image processing concept, and took real digital images of 10 pedestrian streets to verify the validity. Mathematical analysis of subjective and objective indexes showed that street width/height ratio, street width, sky openness index, visual entropy and color richness index could refl ect objective visual properties of streetscape(correlation coeffi cient r > 0.633, signifi cance P < 0.05); visual complexity accounted for the highest percentage in the evaluation conclusion(22.6%), so it was the most signifi cant infl uence factor.