The invention provides a prediction data-based gas balancing and optimal scheduling method, a prediction data-based gas balancing and optimal scheduling device and a prediction data-based gas balancing and optimal scheduling system. The method comprises the following steps: acquiring data needed by the triggering of a gas system from a scheduling system; predicting a produced gas of each production device in a future preset time period and the energy demand of a boiler of a heating furnace according to the data to obtain prediction data; judging whether the production and demand of the gas system are balanced or not in the future preset time period of each production device according to the prediction data, and when the production and demand of the gas system in the future preset time period of each production device are unbalanced, optimizing a scheduling strategy and scheduling scheme of the gas system in the future preset time period of each production device according to the prediction data; and displaying the optimized scheduling strategy and scheduling scheme of the gas system in the future preset time period of each production device by using a client, so that a scheduler can optimally schedule the gas system. Through the method, the device and the system, the gas system of the petroleum chemical enterprise is optimally scheduled so as to solve problems about energy saving and emission reduction.