A method for producing a filter having partially different apparent densities comprises the steps of assembling at least two kinds of foamed bodies having different cell densities, which are formed of an organic compound such as urethane, into a three dimensional structure, immersing the obtained composite body into a slurry composed of ceramic such as cordierite so that the slurry is attached to the surface of the composite body, and firing the composite body to which the slurry is attached, to burn off the foamed bodies. By selecting the portion to be formed into high density, mechanical strength and exhaust gas purifying efficiency of the filter can be improved.