The invention provides a power grid accident economic loss estimation method and a system based on fault loss electric quantity. The method comprises the following steps: S1, calculating the fault loss electric quantity of each fault line in a power grid accident; S2, obtaining load type characteristics of each fault line; S3, searching a ten thousand yuan output value electric quantity corresponding table according to the load type characteristics and the loss electric quantity of the fault line, and obtaining the economic loss of the fault line. According to the power grid accident economicloss estimation method and the system based on fault loss electric quantity, after a fault of power equipment occurs, according to information provided through short-term load prediction, the reasonable scheduling of the power generation capacity is realized, a forecast and economic and reasonable emergency maintenance scheme is provided for the output requirement of a power plant in operation, the loss caused by the fault is reduced, and the stability of the power enterprise and the society is ensured.