This paper presents a fully integrated W-band multi-channel silicon-based radiometer array in a 65-nm CMOS process. Four channels are integrated to achieve higher resolution and sensitivity. A single channel consists of low noise amplifier (LNA), detector, and analog baseband (ABB), respectively. The four-stage LNA achieves a power gain of 29.9dB, a minimum noise figure (NF) of 5.0dB over the band of interest. The detector achieves responsivity of 2.25 kV/W and 463 pW/√Hz noise equivalent power (NEP). The radiometer achieves a responsivity of 384.5 MV/W, an NEP of 23.4 fW/√Hz, and a temperature resolution (NETD) of 0.226 K with a 1 ms integration time. The total power consumption is 254.6 mW.