Abstract: The emphasis of this paper lies in the quantitative estimation of off-site risk to the public from Xi’an Pulsed Reactor（XAPR）. Off-site consequence model for XAPR nuclear accident was established, and the meteorology data acquired from XAPR site was used as the input parameter with probabilistic theory. The off-site risk to the public of XAPR’s radioactivity release was preliminarily analyzed in application of probabilistic safety assessment at 100 m point of XAPR boundary in radioactivity. The results demonstrate that the conditional probabilities of effective dose exceeding 1 m Sv and 10 m Sv are about 0.652% and 0.0750% respectively in the case of radioactivity release spectrum. The overall frequencies with which individual effective dose 10 m Sv is exceeded is less than 2.20×10-9 a-1, meanwhile the other overall frequency with which individual cancer fatality risk is exceeded is not greater than 1.89×10-6 a-1. Accordingly the draft safety goal of XAPR in this research is met from this quantitative risk. Our initial assessment leads to conclude that the off-site risk to the public from XAPR is extremely low and then the high safety characteristic of XAPR is proved.