A power supply with arc flash protection mechanism, comprising: a first power connector including a plurality of power terminals (111b, 111c, 111d) and a first detecting terminal, wherein said plural power terminals (111b, 111c, 111d) are configured to couple with a plurality of power terminals (121b, 121c, 121d) of a second power connector, and said first detecting terminal is configured to couple with a second detecting terminal of said second power connector and provide a detecting signal indicative of whether said second power connector is being disconnected with said first power connector; a power conversion circuit electrically coupled to said power terminals (111b, 111c, 111d) of said first power connector for receiving an input voltage (V in) and converting said input voltage (V in) into an output voltage (V o); a control unit electrically coupled to said power conversion circuit for controlling the operation of said power conversion circuit; and a connection status detection circuit electrically coupled to said control unit and said first detecting terminal of said first power connector for generating a power connection status signal (V a) to said control unit according to said detecting signal; characterized in that, when said first detecting terminal of said first power connector is disconnected from said second detecting terminal of said second power connector, said power connection status signal (V a) is under disable status and said control unit is configured to control said power conversion circuit not to generate or output said output voltage (V o) to a load according to said power connection status signal (V a) so that no current flows between terminals of said first power connector and said second power connector. a first power connector including a plurality of power terminals (111b, 111c, 111d) and a first detecting terminal, wherein said plural power terminals (111b, 111c, 111d) are configured to couple with a plurality of power terminals (121b, 121c, 121d) of a second power connector, and said first detecting terminal is configured to couple with a second detecting terminal of said second power connector and provide a detecting signal indicative of whether said second power connector is being disconnected with said first power connector; a power conversion circuit electrically coupled to said power terminals (111b, 111c, 111d) of said first power connector for receiving an input voltage (V in) and converting said input voltage (V in) into an output voltage (V o); a control unit electrically coupled to said power conversion circuit for controlling the operation of said power conversion circuit; and a connection status detection circuit electrically coupled to said control unit and said first detecting terminal of said first power connector for generating a power connection status signal (V a) to said control unit according to said detecting signal; characterized in that, when said first detecting terminal of said first power connector is disconnected from said second detecting terminal of said second power connector, said power connection status signal (V a) is under disable status and said control unit is configured to control said power conversion circuit not to generate or output said output voltage (V o) to a load according to said power connection status signal (V a) so that no current flows between terminals of said first power connector and said second power connector.