A new accurate simulation method for mass evacuation using precise human joint models has been developed. To realize more accurate as well as realistic evacuation simulation, first, an adequate parallel programming platform using multi-agent concept has been developed. Second, a precise human body model representing real evacuator has been introduced to improve the accuracy of the evacuation simulation. Then, several significant motion primitives such as go-down stairs motion, strictly necessary for the evacuation, have been derived. Finally, comparing the developed simulation results with real evacuation drill result, the effectiveness of the proposed method for mass evacuation simulation has been clarified.