The development course of Photon Scanning Tunneling Microscopy (PSTM) is introduced. There are two difficult problems in first generation (with single beam) PSTM, which are the spurious image and the mixture of optical image with topography of sample in PSTM imaging. With the method of π symmetry two beams lighting to eliminate the optical spurious image, and the method of AF/ PSTM separating image was used to separate the optical image from topography image of sample. The patent instrument named AF/PSTM (atomic force/photon scanning tunneling microscope) have been successfully developed, with which two AFM images (topography and phase images) and two PSTM images (transmissivity and refractive index images) of sample in once scanning are obtained. The AF/PSTM can limit the spurious effects due to non-isotropic illumination with single beam and can separate the refractive index image and transmissivity image from topography image.