The invention relates to a pre-drying and pyrolytic coupling system with dead steam recovery and an operating method. The system comprises a boiler, a steam turbine, a condenser, a condensate pump anda regenerative system which successively communicate and also comprises a brown coal upgrading system where a steam drier, a flue gas drying furnace, a pyrolyzing furnace and a separator communicatesuccessively. By adjusting the flue gas flows of the pyrolyzing furnace and the flue gas drying furnace through a front adjusting valve and a return branch adjusting valve of the flue gas drying furnace and adjusting the steam extraction parameter through a constant pressure valve and a steam return branch adjusting valve, the target is that the temperature of the pyrolyzing furnace is kept at thebest temperature, the temperature and water content of brown coal at the outlet of the flue gas drying furnace are constant, and the pressure at the inlet of the drier is kept constant; the heated feedwater and the dead steam flow are adjusted through an adjusting valve on a feedwater branch and the dead steam adjusting valves, and the target is that the feedwater flow extracted to a dead steam cooler is great as far as possible and the feedwater is heated to the temperature of feedwater of a deaerator. The system provided by the invention achieves poly-generation of electricity and fuels, and is small in system investment and high in utilization ratio of energy.