Effect of operating conditions including temperature (550-700 ^oC), pressure (22-35 MPa), space velocity (0.03-0.09 h^-1), and reactant concentration (0.3-0.9 M) was investigated on the supercritical water gasification of glucose using a Y-Ni/AC catalyst packed-bed reactor. Operating parameters except for reactor temperature did not give significant influence on the gasification results. Carbon gasification efficiency and hydrogen yield markedly increased from 37.3 %, 1.07 mol/mol to 99.7 %, 6.89 mol/mol, respectively, as reactor temperature increased from 550 to 700 ^oC at 28 MPa and 0.05 h^-1 space velocity. For the same reactor pressure and space velocity, COD destruction was 99.5% at 650 ^oC. A series of supercritical water gasifications of molasse-fermented wastewater showed that complete gasification of biological organic wastes at concentrations of over 30,000 ppm can be achieved using a continuous flow reactor employing the Y-Ni/AC catalyst at temperatures above 650 ^oC.