Failure monitoring apparatus for oxygen sensor

The utility model provides an oxygen sensor failure monitoring device which comprises a wave filtering unit, a differentiation unit, a control unit and an output unit. An input end of the wave filtering unit is connected with an oxygen sensor while an output end thereof is connected with one end of the differentiation unit. The other end of the differentiation unit is connected with the control unit. According to signals collected by the differentiation unit, the control unit controls the output unit to output failure information. The oxygen sensor failure monitoring device is directly installed on the oxygen sensor of a vehicle so as to be capable of real-time monitoring the status of the oxygen sensor.