The invention provides an illumination system for super-resolution micro imaging of cells or tissue in different depth, and belongs to the technical field of optics. The system includes a laser, a light beam generated by the laser passes through an initial lens used for collimation and then enters an initial reflector in sequence, the initial reflector transmits the light beam to a reflector set, a cylindrical mirror is arranged between the initial reflector and the reflector set, the light beam passes through the cylindrical mirror in the Z axial direction to enter the reflector set, zooming is conducted in one of the X axial direction and the Y axial direction of the section of the light beam passing through the cylindrical mirror, the light beam thus becomes a sheet like light beam, the sheet like light beam passes through the reflector set to enter an objective lens, and the sheet like light beam is adjusted into a semi total internal reflection illumination mode. The system solves the problem that the very high background light intensity is caused by using semi total internal reflection illumination or wide field illumination when fluorescence localization micro imaging is conducted on the deep layer of a sample and thus the location process cannot be performed, the imaging depth reaches several microns, the structure is simple and compact, and the system is suitable for a commercial super-resolution fluorescence localization microscopic system.