In-Pd-Co-SnO2 composite nanofibers have been synthesized by an electrospinning method and characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Microsensors with a tiny area of 1x1 mm(2) are fabricated by spinning the nanofibers on sensor substrates. Excellent CH4 sensing properties are found based on the micro-sensors. The sensitivity is up to 13 when the sensors are exposed to 10 ppm CH4 at 140 degrees C, and the response and recovery times are about 8 and 14 s, respectively. High selectivity, good stability, and low power-consumption are also observed in the investigation.