A power supply unit for an aerosol inhaler includes: a first element connected in series to a load and having a first electric resistance value; a second series circuit 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 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, and the other of the non-inverting input terminal and the inverting input terminal is connected to the second series circuit. Each of the first to third electric resistance values is larger than the electric resistance value of the load at a normal temperature or a temperature in a predetermined temperature range.