This study is the first to demonstrate the selectivity quantum well intermixing process by using a femtosecond laser scanning induced disordering technique. The advantages of the femtosecond laser are photochemical machining and the two photon absorption mechanism. The femtosecond laser system can convert writing into the scan to create a nanostructure by adjusting the lens. The effect of power on the band gap shift during laser scanning was investigated. The band gap shift was small and unstable without the heating substrate. A wavelength shift higher than 77.3 nm for the InGaAsP MQW material was obtained at elevated temperatures.