China's water rights trading system is becoming mature, but its pricing as the key issue has not yet a rational standard. This paper, aiming at providing theoretical basis for reforming China's water rights trading price and at exploring an appropriate price and at researching the possible issues in water rights trading market, selects Murry-Darling stream water rights trading data during July 2008 to July 2019 to establish a transferred bi-district and tri\|lagging Markov model, which is used to study the fluctuated water rights trading price at different districts in Murry-Darling region. There are two statuses in water rights trading price, highly and lowly fluctuated,with almost same duration. Fluctuation of price is of inertance, not only subject to the changes of natural conditions, but also closely related to Australia's policies. Predicted water rights trading price by MS-VAR model offers references for the both trading sides and for government to make decision. This paper presents suggestions on establishing a sound alerting system for water rights trading price to guarantee rational water rights trading price.