The invention discloses an epitaxial wafer growth online real-time detection method which belongs to the technical field of semiconductor material manufacturing equipment. According to real-time Raman scattering spectroscopy data corresponding each epitaxial wafer, band gap, micro structure and component information of each epitaxial wafer can be in real time analyzed, and wavelength deviation of each epitaxial wafer can be in real time feedback, so that growth information of each epitaxial wafer can be in real time on line detected. The parameters are easy to coordinate consistently, real-time detection data amount is obviously decreased, and the epitaxial wafer growth online real-time detection method can reduce loss caused by poor quality and scrapping of the epitaxial wafer.