：The dual-wavelength lasing from vertical external cavity surface emitting laser (VECSEL) is realized by the large gain spectra and cavity mode detuning，and the stable external cavity is designed. The emission wavelength can be switched between single-wavelength lasing and dual-wavelength lasing according to our simulation results，and three operation modes are proposed and proved by our experiments. The side-mode of VECSEL with side-mode wavelength appears when the