The development of a lasing wavelength switch, particularly from a singleinorganic gain material, is challenging but highly demanded for advancedphotonics. Nonetheless, all current lasing emission of inorganic gainmaterials arises from band-edge states, and the inherent fixed bandgaplimitation of the band-edge system leads to the inaccessibility of lasingwavelength switching from a single inorganic gain material. Here therealization of a single inorganic gain material-based lasing wavelength switchis reported by proposing an alternative lasing emission strategy, that is, lasingemission from surface gain. Previous efforts to achieve surface-gain-enabledlasing emission have been hindered by the limited gain volume provided bysurface states due to the broad emission bandwidth and/or low emissionefficiency. This challenge is overcome by introducing extended surface bandsonto the surface of sulfur quantum dots. The extended surface bandscontribute to a high photoluminescence quantum yield and narrow emissionbandwidth, thereby providing sufficient gain volume and facilitatingstimulated emission. When combined with whispering gallery modemicrocavity, surface gain enabled lasing emission manifests an ultralowthreshold of 8.3 μJ cm⁻² . Remarkably, the reconfigurable perturbation tosurface gain, facilitated by molecular affinity, allows for the realization of thelasing wavelength switch from a single inorganic gain material.