A novel DC offset cancellation programmable gain amplifier was presented for RF identification receiver in 0.18 μm 1P6M CMOS process.The single-stage PGA exhibits-10 to 20 dB gain range with 2 dB step and 0.3 dB gain error.The DC offset is observed as 2% and 39.4 nV/√Hz input referred noise at 40 kHz is achieved at the same time by inserting a filter in the DCOC loop.