Objective To study the rule of aerosol deposition in human upper respiratory tract and analyze the impact of respiratory pattern on aerosol deposition. Methods A computer model of human upper respiratory tract was established first. CFD (computational fluid dynamics) method was then used to numerically simulate the aerosol deposition within the human upper respiratory tract and the rule of aerosol deposition was analyzed. Results The efficiency of aerosol deposition in human upper respiratory tract was improved with the increase of inertial parameter. The breathing intensity and aerosol property had little impact on the pattern of aerosol deposition, which was at most in larynx due to the inertial impact and turbulent dispersion. Under the mode of cyclic inhalation, the aerosol deposition efficiency was higher at unsteady respiratory than that at steady respiratory, at cyclic inhalation than at cyclic exhalation. Conclusions Inertial impact is the main key deposition mechanism for micro aerosol, while turbulent dispersion, secondary flow and recirculation flow have an equally important impact on aerosol deposition in human respiratory tract.