The invention relates to the technical field of building decoration equipment, and discloses an auxiliary mounting bracket for water and electricity mounting. The auxiliary mounting bracket comprises a base, wherein a vertical rod I is fixedly connected to the base, a balancing device, a pipeline temporary storage device, a lifting clamping device, a lifting power device, a horizontal rotating angle fixing mechanism and a releasing device are arranged on the vertical rod I, a second standpipe rotates, the part, in a first standpipe, of the second standpipe extends to push a first rotary disc to move towards a roof, when balls on the first rotary disc makes contact with the roof, an installation worker stands on a first supporting plate, the balls make contact with the roof to form a fulcrum, the worker on the first supporting plate exerts downward force on the first supporting plate, supporting force applied to the balls by the roof is used for balancing the gravity of workers on the first supporting plate, supporting objects on the ground are effectively reduced by transferring supporting points for balancing the gravity of the workers on the first supporting plate to the roof from supporting of the ground, the utilization rate of the ground is increased, stumbling to the workers on the ground is reduced, and the safety effect is improved.