An image processing method of two-photon structured illumination point scanning microscopy is disclosed. The image processing method includes the following steps: providing a laser light source performing scanning and recording and performing image reconstruction. The laser light source, which has photon energy that is half of the energy needed to let a molecule of a sample make a transition from ground state to a first excited state, is focused onto a focal plane of the sample. Then, the laser light source is accompanied with an image recording system to perform a plurality of segmented scanning and image recordings on the sample to generate a plurality of structured illumination images. Those structured illumination images are reconstructed to generate microscopic image of the sample. With the implementation of the present invention, the interference from image signal on the non-focal plane can be effectively reduced, thereby enhancing the resolution of microscopic image.