This paper describes a monolithic GaAs FET active bandpass filter utilizing negative resistance elements, The negative resistance element was realized with a common-drain FET with series inductive feedback and the measured output impedance characteristics are given, The fabricated monolithic forth-order filter showed an insertion loss of 0.7 dB at 4.85 GHz and a 3-dB bandwidth of 50 MHz with a de power consumption of 7.5 mW.