The invention relates to a ferrite type phase shifter and an accelerator. The phase shifter includes a waveguide, a ferrite bar, a first coil, a second coil, a first power source and a second power source; the ferrite bar is arranged in the waveguide; the first power source is used for providing direct-current voltage to the first coil, so that a constant magnetic field can be generated; the second power source is used for providing pulse voltage for the second coil, so that a pulse magnetic field can be generated; the constant magnetic field and the pulse magnetic field are superimposed so as to form a composite magnetic field; and the ferrite bar is applied to the composite magnetic field, so that phase change can occur on microwaves which pass through the waveguide. According to the ferrite type phase shifter of the invention, the two coils and two corresponding power sources are adopted; the two power sources respectively provide the direct-current voltage and the pulse voltage; the ferrite can receive the superposition of the two kinds of voltage, so that the stable composite magnetic field can be generated; and therefore, the loss of microwave transmission can be avoided. The phase shifter can achieve 180-degree phase change through controlling the voltage.