Outdoor surfaces are usually dirty surfaces. Ice accretion on outdoor surfaces could lead to serious acci-dents. In the present work, the superhydrophobic surface based on 1H, 1H, 2H, 2H-Perfluorodecanethiol(PFDT) modified Ag/PDMS composite was prepared to investigate the anti-icing property and self-cleaning property at temperatures below freezing point. The superhydrophobic surface was deliberatelypolluted with activated carbon before testing. It was observed that water droplet picked up dusts on thecold superhydrophobic surface and took it away without freezing at a measuring temperature of −10◦C.While on a smooth PFDT surface and a rough surface base on Ag/PDMS composite without PFDT modi-fication, water droplets accumulated and then froze quickly at the same temperature. However, at evenlower temperature of −12◦C, the superhydrophobic surface could not prevent the surface water fromicing. In addition, it was observed that the frost layer condensed from the moisture pay an important rolein determining the low temperature self-cleaning properties of a superhydrophobic surface.