All-solid-state dual-wavelength lasers are widely used in differential absorption lidar, precision measurement, biomedicine, terahertz generation, etc. Dual-wavelength lasers can be obtained through direct generation in single and dual laser gain media based on stimulated radiation, or laser pumped optical parametric oscillators. The main technical approaches and developments on dual-wavelength laser generation are introduced. The methods to tune the power ratio between two wavelengths and manipulate the pulse operating mode are summarized. The merits and demerits of these methods are analyzed, and the outlook is also given.