The invention discloses an interconnected power grid decentralized and collaborative risk dispatching method based on risk node price, comprising the following steps: an interconnected power system is decomposed into multiple regional subsystems; the tie-line transmission power between the regional subsystems is initialized to zero; the regional subsystem dispatching centers solve a risk-based security constrained economic dispatching problem according to the latest tie-line transmission power value, and acquire the risk node price on each common link point; whether the adjacent regional subsystems have the same risk node price on a coupling common link point is judged through comparison; if the adjacent regional subsystems have different risk node prices on the coupling common link point, the adjacent regional dispatching centers compare the risk node price curves to adjust the tie-lines so as to balance the risk node prices on the coupling common link point; and if all the connected regions have the same risk node price on the coupling common link point, iteration ends, and a final dispatching plan is obtained. Triple-win of an interconnected power system in economy, security and risk is realized.