The invention relates to transformation of a No. 2 unit condensate fine treatment system in a power plant, in particular to a condensate fine treatment high-temperature running system having heat supply and pure condensation modes. Three butyl rubber (resistant to the temperature of 100-120 DEG C)-lined high-speed mixing beds are arranged at the positions of three original high-speed mixing beds in a No. 2 unit on the basis of current equipment; the original three natural rubber-lined high-speed mixing beds are changed into resin storage tanks which are arranged on the zero expansion ends of a No. 2 unit room and moved to the southern sides of the original high-speed mixing beds, and a resin conveying pipeline, a flushing water pipeline and a compressed air pipeline are connected between the resin storage tank and the three newly-added high-speed mixing bed equipment, so that switching and conveying of home-made resin and imported resin under heat supply and pure condensation working conditions are facilitated. Thus, normal work of condensate fine treatment equipment of over high temperature during back-pressure running of the No. 2 unit during a heat supply period is ensured; meanwhile, normal running and regeneration of a condensate fine treatment system of a No. 1 unit is not influenced.