The O3++He collision processes are studied ultilizing a classical trajactory Monte-Carlo (CTMC) method. The initial microcanonical distribution is modified by using eleven different ionization thresholds of electrons in tht target. The total cross sections of all processess as functions of the projectile energy are calculated. For a test, the process of He2++He is calculated and the agreement with experiment is improved by the modified distribution.The total cross sections of O3++He including single- and double-electron ionization and transfer ionization are obtained in the energy range from 3 keV/u to 1 MeV/u, which are found in good agreement with the experiment. But there exists some large difference for the ratio of transfer ionization to single-electron capture, which requires further theoretical and experimental investigations.