Ultrawideband CMOS low noise amplifier (LNA) using lossy LC ladder is proposed. A lossy LC ladder matching network is combined with conventional inductive degeneration and provides both gain and noise match over multioctave bandwidth. The bandwidth is further enhanced by shunt peaking technique. The explicit formulas are derived in this work to determine the values of resistor and LC ladder elements to meet the gain and noise match conditions. The LNA achieves 10.8-dB gain with a 3-dB bandwidth from 1.6 to 13.2 GHz and a minimum noise figure of 3.4 dB under the power consumption of 22 mW.