Ni1-xCoxO-Ce0.8Sm0.2O1.9 (SDC) composite is investigated as an anode material for solid oxide fuel cells with methanol as fuel. The interaction between NiO and SDC phases is enhanced by Co. Besides, Co reduces the particle size and improves the dispersion of Ni1-xCoxO by inhibiting the grain growth of NiO, which results in larger three-phase boundary in the anode layer. The Ni0.9Co0.1-SDC anode shows the lowest polarization resistance. A maximum power density of 675 mW cm(-2) is achieved by a single cell with Ni0.9Co0.1-SDC anode and SDC-carbonate composite electrolyte at 700 degrees C. Co also increases the resistance to carbon deposition of the anode and decreases the graphitization degree of deposited carbon with methanol as fuel. The cell with the Ni0.9Co0.1-SDC anode exhibits a stable performance during a 500-min discharge period.