The invention discloses a loudspeaker box power amplifier power supply circuit. The loudspeaker box power amplifier power supply circuit comprises a power supply input circuit (1), a primary rectifying filter circuit (2), a voltage stabilizing circuit (3) and a primary transformer (4). The power supply input circuit (1) is connected with the primary rectifying filter circuit (2). The voltage stabilizing circuit (3) is connected with the primary rectifying filter circuit (2). The primary transformer (4) is connected with the voltage stabilizing circuit (3). The loudspeaker box power amplifier power supply circuit further comprises at least one secondary rectifying filter circuit (5) and at least one secondary voltage transformation circuit (6). Each secondary rectifying filter circuit (5) is connected with the primary transformer (4). The secondary voltage transformation circuits (6) are connected with the secondary rectifying filter circuits (5) in a one-to-one corresponding mode respectively. The output ends of all the secondary voltage transformation circuits (6) are power supply output ends. The loudspeaker box power amplifier power supply circuit is simple in structure, and all output power supplies are stable and do not interfere with one another.