Method for manufacturing honeycomb structural body and method for manufacturing exhaust gas converting apparatus

A method for manufacturing a honeycomb structural body comprising a honeycomb unit, the method comprising:

• obtaining a honeycomb molded body comprising a compound containing a phosphate group zeolite and an inorganic binder, the honeycomb molded body having a plurality of through holes that are defined by cell walls and arranged in a longitudinal direction of the honeycomb molded body;
• drying the honeycomb molded body;
• firing the dried honeycomb molded body to obtain the honeycomb unit;
• and
• storing at least one of the honeycomb unit and the dried honeycomb molded body so that a difference in moisture content is approximately 5 mass % or less between a moisture content of the cell walls at a center part of a cross section perpendicular to the longitudinal direction and a moisture content of the cell walls at an outer periphery part of the cross section perpendicular to the longitudinal direction,
• wherein the storing step of the dried honeycomb molded body comprises allowing air to flow through the plurality of through holes, the air having humidity that is approximately 20% RH or more and approximately 60% RH or less.