Catalytic biomass gasification is an environmentally benign solution to energy problems. A series of Ni catalysts on mesoporous SBA‐15 are synthesized with various La2O3 loadings. The catalytic activity of unpromoted Ni/SBA‐15 catalyst indicates that it has a high carbon formation rate, resulting in fast deactivation. In contrast, addition of La2O3 to Ni/SBA‐15 catalyst helps to remove deposited carbon by formation of oxycarbonate, resulting in higher CO production. A 1 % La doping in the Ni/SBA‐15 catalyst is sufficient to achieve high activity and stability in biomass gasification with various raw materials and in the steam reforming of toluene as a tar model compound. The combination of small metal particle size, high metal dispersion, high surface area of SBA‐15, the crucial role of La in carbon removal, and the novel synthesis method result in a highly active, stable, and effective 1 % La‐Ni/SBA‐15 catalyst for biomass gasification.