To provide a mesh sealing material of a ceramic honeycomb filter in which a mesh sealing material is injected into the determined passage using a tubular member to form a mesh sealing part wherein the fluidity of the mesh sealing material can be secured and also the shape of the mesh sealing part can be maintained, and to provide a mesh sealing method.

The mesh sealing material of the ceramic honeycomb material, in which the mesh sealing material is injected into the determined passage of a ceramic honeycomb structure having many passages surrounded by a porous partition wall using the tubular member, wherein the mesh sealing material is obtained by blending a ceramic material, at least an organic binder, a polymer surfactant and water, also the organic binder is such methyl cellulose and/or hydroxy propylmethyl cellulose that a 2% aqueous solution has a viscosity of 2,000 mPa s or below at 20°C, and the polymer surfactant is a polycarboxylic-acid type polymer surfactant.