The invention relates to a high-collimation solar simulator optical system with an auto-collimation aiming system, belonging to a solar simulator optical system in the technical field of optics design and aiming at solving the technical problem of providing a high-collimation solar simulator optical system with the auto-collimation aiming system. The high-collimation solar simulator optical system with the auto-collimation aiming system comprises a xenon lamp source, an ellipsoid condenser, a plane mirror, an optics integrator assembly, a first dispersion prism, a second dispersion prism, an emission reticle, an LED light source, an aiming reticle, an ocular lens and a collimator objective. On the basis of the traditional high-collimation solar simulator optical system, an auto-collimation aiming system is added on an optical path of the optical integrator assembly, wherein the auto-collimation optical system comprises a first dispersion prism, a second dispersion prism, an emission reticle, an LED light source, an aiming reticle and an ocular lens. The invention can ensure more accurate zero calibration so as to eliminate the man-made influence and achieve better experimental effect.