An instrumentation amplifier includes: a first input stage configured to shift a level of a first input voltage applied to a first input terminal and to output the level-shifted voltage; a second input stage configured to shift a level of a second input voltage applied to a second input terminal and to output the level-shifted voltage; a first resistor configured to generate a differential current corresponding to a difference between the voltage output from the first input stage and the voltage output from the second input stage; a second resistor configured to convert the differential current into a first output voltage; a third resistor configured to convert the differential current into a second output voltage; a first output stage configured to output the first output voltage from a first output terminal; and a second output stage configured to output the second output voltage from a second output terminal.