Lead halide perovskites are attracting intense research interest due to their high energy conversion efficiency and tunable optoelectronic properties. In this study, we demonstrate an environment-friendly one-drop self-assembly and ion-exchange methods for preparation of CsPbBr3 perovskite nanowires (NWs). High-quality NWs can be obtained with very small doses of required material. In order to expand the emission band of the NWs, an ion exchange process was utilized to substitute the bromide component in CsPbBr3 NWs with other halogens, and emission over a band of 420-710 nm was successfully achieved. The NWs realized lasing in the range of 420-560 nm, and the typical thresholds for CsPbBr3 and CsPbCl3 NWs were 63.86 μJ/cm2 and 68.2 μJ/cm2, respectively. In addition, the NWs also showed robust stability under the continuous irradiation with the high energy laser pulses in ambient atmosphere.