A power supply unit and a load , the power supply unit being suitable for an aerosol inhaler having a power supply capable of performing discharge to said load , whereby said load is able to heat an aerosol generation source and whose temperature and electric resistance value have a correlation, the power supply unit for the aerosol inhaler comprising: a first element having a first electric resistance value connected in series to the load ; a second series circuit (C2) including a second element having a second electric resistance value and a third element connected in series to the second element and having a third electric resistance value, and connected in parallel with a first series circuit (C1) including the load and the first element ; and an operational amplifier in which one of a non-inverting input terminal and an inverting input terminal is connected to the first series circuit (C1), and the other of the non-inverting input terminal and the inverting input terminal is connected to the second series circuit (C2), characterised in that the electric resistance value of the load in a temperature range of -10°C to 300°C is smaller than the first electric resistance value, the second electric resistance value and the third electric resistance value; and the power supply unit further comprises: a first connection circuit configured to supply current to the first series circuit (C1) and the second series circuit (C2); and a heating circuit comprising a switch and wiring and configured to supply the load with a current larger than a current flowing through the load when the heating circuit is turned off and a current is supplied by the first connection circuit. a first element having a first electric resistance value connected in series to the load ; a second series circuit (C2) including a second element having a second electric resistance value and a third element connected in series to the second element and having a third electric resistance value, and connected in parallel with a first series circuit (C1) including the load and the first element ; and an operational amplifier in which one of a non-inverting input terminal and an inverting input terminal is connected to the first series circuit (C1), and the other of the non-inverting input terminal and the inverting input terminal is connected to the second series circuit (C2), characterised in that the electric resistance value of the load in a temperature range of -10°C to 300°C is smaller than the first electric resistance value, the second electric resistance value and the third electric resistance value; and the power supply unit further comprises: a first connection circuit configured to supply current to the first series circuit (C1) and the second series circuit (C2); and a heating circuit comprising a switch and wiring and configured to supply the load with a current larger than a current flowing through the load when the heating circuit is turned off and a current is supplied by the first connection circuit. a first connection circuit configured to supply current to the first series circuit (C1) and the second series circuit (C2); and a heating circuit comprising a switch and wiring and configured to supply the load with a current larger than a current flowing through the load when the heating circuit is turned off and a current is supplied by the first connection circuit. <EOS>