The invention discloses an LPM speed adjusting module for an automobile air conditioner air blower. An operational amplifier and a dual-power MOSFET are adopted to be combined with a discrete electronic component for building an analog circuit, and the LPM speed adjusting module with the comprehensive function for the air blower is achieved, wherein the dual-power MOSFET is sufficiently and flatly attached to a heat dissipater for dissipating heat emitted by the dual-power MOSFET in the working process so as to work at the quite safe and reliable rated working environment temperature. The LPM speed adjusting module internally has a VB+ voltage switch control function besides the stepless speed adjustment function for the air speed of the air blower so as to reduce static consumption current in the silence state, and therefore automobile battery electricity loss is prevented. Internal VB+ voltage is turned off when the LPM speed adjusting module is in the zero air speed gear to achieve no electric charge internally. The LPM speed adjusting module further has the main functions of overvoltage protection, overtemperature protection, current limiting protection, locked rotor protection and short circuit protection, and is stable, reliable, low in manufacturing and material cost and strong in anti-electromagnetic interference ability.