[en] The SR (Synchrotron Radiation) ring with high brightness is planned as a next generation synchrotron radiation facility. In the electron injector of the SR ring, the electron beam generated by the thermionic gun is accelerated by the 238 MHz accelerating cavity and is compressed by the 476 MHz Sub Harmonic Buncher (SHB) to obtain a low emittance beam with a bunch length of 5 ps. Mitsubishi Heavy Industries Machinery Systems, Ltd. (MHI-MS) has fabricated the 238 MHz accelerating cavity and the 476 MHz SHB for use in the demonstration test of high brightness electron beam production. Both the 238 MHz accelerating cavity and the 476 MHz SHB are standing wave type cavities of reentrant structure. In the low-power test, the center frequency was adjusted by the tuner at the operating temperature, and Q₀ values of 23062 and 25743 were obtained, respectively. Four C-band disk-loaded type accelerating structures were also manufactured. In this paper, we report the fabrication, low-power test results of the 238 MHz accelerating cavity, the 476 MHz SHB, and C-band disk-loaded accelerating structures are shown. (author)