The invention discloses an air conditioner driver voltage source detection circuit and method. The circuit comprises a detection unit and a processing unit; the detection unit includes a positive detection end, a negative detection end, a first unidirectional circuit, an energy storage circuit and a voltage-controlled isolation output circuit; the positive detection end is connected with the negative detection end through the first unidirectional circuit and the energy storage circuit; the voltage-controlled isolation output circuit is connected in parallel with the energy storage circuit; and the output end of the voltage-controlled isolation output circuit is connected with the processing unit. According to the air conditioner driver voltage source detection circuit and method of the invention, the specific value of an input voltage is not required to be determined; the first unidirectional circuit and the energy storage circuit are used in combination; the unidirectional circuit is fully turned on under direct current, and the turn-on frequency of the unidirectional circuit under alternating current is consistent with the frequency of the alternating current; the voltage of the energy storage circuit can reflect the type of the inputted voltage and the frequency of the alternating current; and the voltage-controlled isolation output circuit outputs voltage detection signals which reflect the type of the voltage and the frequency of the alternating current. The air conditioner driver voltage source detection circuit and method of the invention have the advantages of simple structure, low cost and high reliability.