To remove a fly ash easily even though the fly ash stuck to a surface is solidified by a method wherein a fin is radially established on a dedusting surface of a filter main body.

A filter main body 2 is formed in a closed-end cylinder, and many fins 3 are radially established on its outer side surface. A fin 3 is formed in a form of a long paper strip, provided over the whole length of the outer side surface 5 integrally with the filter main body 2, and its width is designed by considering a stuck amount of a fly ash, a cleaning cycle, or the like. A dedusting filter 1 has a structure wherein a ceramics layer is vapor deposited on a fiber surface of a fiber molded body of a closed end cylinder with a flange molded with one kind or two or more kinds of fibers selected from a group comprising a silicon carbide fiber, a silicon nitride fiber, an alumina fiber, an alumina silica fiber, and a carbon fiber. A fly ash A deposited on the outer side surface of the filter main body 2 is fractionized with adjoining fins 3, 3. The solidified fly ash can be easily removed from the filter by adding impact from outside with hammering etc., or by a back wash with a high pressure gas.