A pulverized coal injection increases the accumulation of fines in a blast furnace. The accumulation of fines in the lower part of the blast furnace diminishes the size of the raceway depth and gas flow into the deadman and, as a result, affects the steady state condition of the blast furnace. The state of the blast furnace, which depends on the gas and solid flow, chemical reactions, mass transfer and heat transfer, is numerically analyzed using a FEM (finite element method). But the ore reduction index model, which estimates the chemical state of ore in blast furnace, is made using Forward Euler method. The decrease in both the size of the raceway depth and the gas flow into the deadman results in increasing pressure drop and lowering the average temperature in the blast furnace. However the reduction of gas flow into deadman affects in only the lower part of the furnace, but the diminution of the raceway depth decreases the average temperature in the entire furnace, even though the solids on the upper raceway become hotter due to increasing gas flux through the raceway. So, the melting position is lowered in axial direction at center of blast. As a result the length of the cohesive zone is shortened to give permeability resistance on the gas flow and to make the furnace operation unstable.