The invention discloses a device and method for generating intermediate-temperature steam by uniting solar heat collection and an electric boiler. A solar heat collector (the solar heat collector comprises a cascaded solar heat collection array, a core component comprises an intermediate-temperature tube, a cooper adjustor, a reflector and a header assembly) and the electric boiler are united to be utilized to replace use of a coal burning boiler or an oil burning boiler, the use ratio of solar energy is enhanced, the electric quantity used at peak time is reduced, a united energy supply system is built, and gradient utilization of the energy is achieved.