According to the coupled wave equation of grating layer controlling light wave propagation, a sub-wavelength grating guided mode resonance filter was designed. By tuning the thickness of air layer, the filter can tune the wavelength of 75 nm, and the linewidth is below or the same as 1 nm. The resonant wavelength tunable filter is integrated with a Vertical Cavity Surface Emitting Laser (VCSEL) of central wavelength of 1.55 μm, creating a lasing wavelength tunable VCSEL. It is found that the tuning range of lasing wavelength is identical to that of resonant wavelength tunable filter, and the wavelength of lasing wavelength tunable VCSEL is equal to that of resonant wavelength tunable filter at the same thickness of air layer. The VCSEL can choose both the lasing wavelength and the transverse mode of output.