Pig disease is major factor affecting pork price in Yunnan Province. This study utilized component decomposition method to identify the real price of pork and analyzed price fluctuation. A vector auto-regressive model was used to investigate the stochastic impact of pig epidemic on real price of pork. The results showed that pork price had significant seasonal and cyclical features; when Stochastic of pork price triggered a standard deviation size impact, the pork price responded to stochastic impact from January, and reached the peak in April, furthermore, price returned to normal after 24 months. Pig epidemic was a significant factor the affects pork price. The stochastics contributed greater over time, and stabilized at 44.46% after 10 months.