Abstract: The development of the fourth generation diffraction-limited synchrotron radiation source (DLSR) is introduced. Many key technologies are involved in the initial stage. This paper mainly discusses the special power supply technologies involved in DLSR, including high-voltage nanosecond fast pulsed power for injection and extraction system, high-precision magnet power supply, bipolar dynamic corrector power supply, high-power klystron modulator, etc. The parameter requirements, key techniques and solutions of these power supplies are introduced respectively.