We present a novel single-chip thermopile sensor array for mid-infrared room temperature imaging. The array is fabricated on a single complementary metal-oxide-semiconductor (CMOS) dielectric membrane, composed of single-crystal silicon (Si) p+ and n+ elements, and standard CMOS tungsten metal layers for thermopile cold junction heatsinking, significantly reducing the chip size and simplifying its processing. We demonstrate a 16×16 pixel device with 34 V/W responsivity and enhanced optical absorption in the 8-14 μm waveband, with a suitable performance for gesture recognition and people-counting applications. Our simple, low-cost sensor is an attractive on-chip array for a variety of applications in the mid-infrared spectral region.