The invention discloses a method for controlling a single-side-controllable parallel winding open type permanent magnetic synchronous generator. The method comprises the steps of performing Clarke andPark transformation on current acquired three-phase stator current by means of an acquired rotor position angle of a winding opening type permanent magnetic synchronous motor system, and obtaining current at current time; calculating the predicated current at next time according to the obtained current at current time; obtaining a voltage error signal according to comparison between preset load voltage and actually measured load voltage; performing voltage outer-ring adjustment on the obtained voltage error signal, thereby obtaining reference current at the next time; and evaluating an errorbetween the reference current at the next time and the predicated current at the next time according to a cost function, and selecting a set of switching signals which minimize the value of the cost function for acting on a three-phase converter. The method for controlling the single-side-controllable parallel winding open type permanent magnetic synchronous generator has advantages of reducing parameter adjusting complexity of a PI adjustor, and improving dynamic system performance through no bandwidth restriction of the current.