The gasification industries make use of biomass residue as feedstock to produce synthesis gas, but the gasification of this waste biomass generates tons of ash everyday. Performance properties and agglomeration behavior of ccob ash (CCA) collected from the gasification of ccobs in a pilot-scale gasification station were investigated by using some experimental methods. Based on the chemical composition results, the agglomeration tendency of CCA from combustion and gasification process was also analyzed. Chemical analysis shows that the fly ash is mainly composed of inorganic matters formed by K, Mg, Ca, Na, Fe, Al, S, etc. The agglomeration characteristics indicate that the slagging degree increases with the increase of ashing temperature, and the slagging tendency of these CCA samples from gasification or combustion is different with various slagging indices. All CCA samples from combustion or gasification can cause slagging/fouling problems in thermal conversion systems. The applications of CCA are closely related to its performances, and CCA has the potential to be used in various fields, for example, as a material for ceramic products and activated carbon, as an adsorbent, as a crude fertilizer, and as a structural material.