Positive and negative output ends of a differential circuit in a sample hold circuit are connected to capacitors through switch circuits. Further, collectors of two input transistors of a buffer circuit connected to the sample hold circuit are driven by a collector driving differential circuit, so as to make the collector.multidot.base voltages of two input transistors same to each other. Consequently, a stable sample hold circuit having an arbitrary gain can be provided. In addition, drifts of outputs from two capacitors in the sample hold circuit can be made equal to each other by the buffer circuit.