In this paper, a high bandwidth, low power consumption, and high gain-flatness distributed amplifier (DA) is presented. It is fabricated using a standard 0.13-μm CMOS process with six metal layers. The DA has a unity-gain cutoff frequency of 40GHz. The DA chip achieves measured results of 8dB gain, with a gain flatness of ±1-dB over the bandwidth of 10-30-GHz. And, the noise figure is between 4.2 and 5.7dB. Power consumption and current of the distributed amplifier are 25.2mW and 21mA at 1.2V supply voltage, respectively. Compared with traditional distributed amplifiers, using the cascade distributed amplifier can obtain more gain and better flatness.