A power supply unit for an aerosol inhaler, the power supply unit comprising: a power supply able to discharge power to a load for generating an aerosol from an aerosol generation source; and a charger configured to convert power, which is supplied from an external power supply, into charging power for the power supply, wherein the charger includes an information input part, and is configured to supply one of a first charging voltage and a second charging voltage lower than the first charging voltage to the power supply, based on an input value which is input from the information input part, the power supply unit comprising a fixed resistor having a fixed resistance value and connected between the information input part and a main negative bus line or a ground line, characterized in that the power supply unit is configured to apply, to the fixed resistor, a voltage of a fixed value which is predetermined as one input value to be input to the information input part, and the fixed value is a value for supplying the second charging voltage to the power supply, the power supply unit further comprising: a switch configured to perform switching between a state where the fixed value is input to the information input part and a state where the fixed value is not input to the information input part; wherein the switch is provided, in parallel with the fixed resistor, between the information input part and the main negative bus line or the ground line, such that when the information input part and the main negative bus line or the ground line are connected by the switch, the fixed value is not input to the information input part, and when the information input part and the main negative bus line or the ground line are disconnected by the switch, the fixed value is input to the information input part. a power supply able to discharge power to a load for generating an aerosol from an aerosol generation source; and a charger configured to convert power, which is supplied from an external power supply, into charging power for the power supply, wherein the charger includes an information input part, and is configured to supply one of a first charging voltage and a second charging voltage lower than the first charging voltage to the power supply, based on an input value which is input from the information input part, the power supply unit comprising a fixed resistor having a fixed resistance value and connected between the information input part and a main negative bus line or a ground line, characterized in that the power supply unit is configured to apply, to the fixed resistor, a voltage of a fixed value which is predetermined as one input value to be input to the information input part, and the fixed value is a value for supplying the second charging voltage to the power supply, the power supply unit further comprising: a switch configured to perform switching between a state where the fixed value is input to the information input part and a state where the fixed value is not input to the information input part; wherein the switch is provided, in parallel with the fixed resistor, between the information input part and the main negative bus line or the ground line, such that when the information input part and the main negative bus line or the ground line are connected by the switch, the fixed value is not input to the information input part, and when the information input part and the main negative bus line or the ground line are disconnected by the switch, the fixed value is input to the information input part. a switch configured to perform switching between a state where the fixed value is input to the information input part and a state where the fixed value is not input to the information input part; wherein the switch is provided, in parallel with the fixed resistor, between the information input part and the main negative bus line or the ground line, such that when the information input part and the main negative bus line or the ground line are connected by the switch, the fixed value is not input to the information input part, and when the information input part and the main negative bus line or the ground line are disconnected by the switch, the fixed value is input to the information input part.