The invention relates to a dual-wavelength laser based on stimulated Raman scattering of aqueous ethanol solution. The dual-wavelength laser comprises a pump source, a diaphragm, a first window, a Raman box, a second window and a first color filter which are sequentially placed along an optical path. The first window, the Raman box and the second window are sequentially sealed and connected, and the Raman box is filled with an ethanol aqueous solution. The pump source generates laser light, the laser light passes through the diaphragm, the first window, and is incident into the Raman box containing the ethanol aqueous solution. At the same time, ethanol and water respectively generate stimulated Raman laser to form a dual-wavelength stimulated Raman laser with frequency difference. The first color filter filters out the pump light and transmits the required dual-wavelength laser. The pump source and the working medium of the invention have a wide selection range and flexible wavelengthselection. The threshold for resistance to light damage is high. The laser diameter and medium length are flexible. The cost is low, the dual-wavelength laser is easy to produce, is simple to debug,is wide in application range, can be used for fine laser spectroscopy, differential absorption laser radars, laser communication, environmental detection, fiber optic communication, nonlinear opticalfrequency conversion, etc.