The ambient light and transmission of light source regions and non-light source regions have different physical properties in nighttime scenes. However, existing nighttime dehazing algorithms ignored this phenomenon and got oversaturated results looked like in the daytime. In this paper, we propose a nighttime dehazing method using fused ambient light and transmission based on saliency detection. We first propose a multi-scale saliency detection algorithm to differentiate light source regions and non-light source regions. Then we estimate ambient light and transmission of the two regions based on different methods to acquire the fused ambient light and fused transmission. Finally, we get the haze-free results based on the nighttime imaging model. Experimental results show that our method outperforms other state-of-the-art methods in color recovery and our haze-free results still look like in the nighttime.