The invention discloses a closed loop dual-mode reduced-order model prediction control method for a Buck type DC-DC converter. A closed loop dual-mode reduced-order model prediction control algorithm is adopted; a closed loop feedback gain coefficient is introduced in a rolling optimization process so as to ensure the stability of the control system; meanwhile, the dual-mode structure is subjected to order reduction by adopting an SVD decomposition method, so that the overall calculation process is simplified twice in order to reduce the online calculated amount; and in addition, an off-set free idea is adopted in the algorithm implementation process, so that the output can stratify a set point value, and the control for the DC-DC converter is realized.