A buffer circuit permitting an input signal to pass and prohibiting the input signal from passing corresponding to an output control signal, including an output switching device, a control portion having a first switching circuit controlling the output switching device into conductive state and a second switching circuit controlling the output switching device into non-conductive state, and controlling the output switching device into the conductive state or non-conductive state corresponding to the input signal and the output control signal, wherein a connecting point between the first switching circuit and the second switching circuit is coupled to the output switching device, and a changing portion connected to the second switching circuit in series and limiting the drive capacity of the output switching device when the output control signal is in an output prohibition state of prohibiting the input signal from passing.