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A compact and reconfigurable low noise amplifier(LNA)is proposed by combining an input transistor,composite transistors with Darlington configuration as the amplification and output tran-sistor,T-type structure composite resistors instead of a simplex structure resistor,a shunt inductor feedback realized by a tunable active inductor(AI),a shunt inductor peaking technique realized by another tunable AI.The division and collaboration among different resistances in the T-type structure composite resistor realize simultaneously input impedance matching,output impedance matching and good noise performance;the shunt feedback and peaking technique using two tunable AIs not only extend frequency bandwidth and improve gain flatness,but also make the gain and frequency band can be tuned simultaneously by the external bias of tunable AIs;the Darlington configuration of com-posite transistors provides high gain;furthermore,the adoption of the small size AIs instead of large size passive spiral inductor,and the use of composite resistors make the LNA have a small size.The LNA is fabricated and verified by GaAs/InGaP hetero-junction bipolar transistor(HBT)process.The results show that at the frequency of 7 GHz,the gain S21 is maximum and up to 19 dB;the S21 can be tuned from 17 dB to 19 dB by tuning external bias of tunable AIs,that is,the tunable amount of S21 is 2 dB,and similarly at 8 GHz;the tunable range of 3 dB bandwidth is 1 GHz.In addition,the gain S21 flatness is better than 0.4 dB under frequency from 3.1 GHz to 10.6 GHz;the size of the LNA only has 760 μm × 1260 μm(including PADs).Therefore,the proposed strategies in the paper provide a new solution to the design of small size and reconfigurable ultra-wideband(UWB)LNA and can be used further to adjust the variations of gain and bandwidth of radio frequency inte-grated circuits(RFICs)due to package,parasitic and the variation of fabrication process and tem-perature.