The Przewalski’s horse (Equus przewalskii) population re-introduced in the Anxi Extra-arid Desert National Nature Reserve in northwest China is a relatively isolated populationwith an extremely low growth rate. In addition, they are facing severe predation pressure as well as inbreeding recession. Hence, to develop a long-term protection strategy is of high urgency. In this study, the reproduction and population viability of reintroduced Przewalski’s horse have been analyzed. The results showed that, (1) the low population growth of reintroduced Przewalski’s horse was caused by both low fertility rate (44.3%) and high foals mortality rate (43.4%). Low reproductive survival rate is mainly influenced by natural enemies' predation and diseases. The Przewalski’s horses exhibited seasonal breeding, 80.9% of foals were born in May and June; (2)We used the Population Viability Analysis modelVORTEX in this case and predicted that the extinction risk of this population is 60% after 100 years. Aminimum population of 200 is required to guarantee a risk less than 10%; (3)The sensitivity analysis showed that wolf attacks have the greatest influence on the extinction risk and final population size, followed by intrinsic factors such as maximum breeding age and fecundity rate; (4) This Przewalski’s Horse population was trapped in a small population effect. The mortality caused by diseases and foal weakness was relatively high (26.5% and 8.82%, respectively). Hence, it is necessary to supplement the population with new individuals to prevent extinction. Some additional strategies, like mitigating wolves’ predation pressure and strengthening foals’s security, can also effectively improve the Przewalski’s horse living condition.