Vanadium oxide uncooled bolometer with gold black absorber of high long-wave-infrared-rays absorption has been fabricated and optimized. The fabrication processes for mirobolometer were developed with surface micromachining below 350°C. We evaluated gold black film reflectance by Fourier transform infrared spectroscopy. Low reflectance shows that gold black has good absorption at 8 to 14 μm infrared window. Detector tests show that a bolometer with gold black absorber, compared with the one without gold black, had better performance, with maximum responsivity and detectivity of 8.4×104 V/W and 6.16×108 cm Hz1/<2/W, respectively, at 13 Hz chopper frequency and bias current 67 μA.