The invention discloses a control method for a 600MW supercritical extraction condensing generating heat supply unit to realize no heat supply cutoff through combined starting of an electric pump after a single steam pump trips out. According to the control method disclosed by the invention, after the single steam pump of the generating heat supply unit trips out, running equipment, such as the steam pump, the electric pump, a steam turbine regulating valve and a coal pulverizing system, respectively and correctly operate; the feed water flow is stabilized to be 1400t/h, the electrical load of the unit is stabilized to be 473MW, and the supplied heat flow is stabilized to be 481t/h, and all parameters tend to be stable, so that the effects less load and even no load of the unit is reduced and the heat supply is not cut off after the single steam pump trips out is realized; the accident that the external heat supply of a power plant is interrupted is avoided; the reliability of the external heat supply of the power plant is greatly improved; a powerful guarantee is provided for local surrounding industrial heat users; the control method has good social benefits and economic benefits.