Abstract: A filler for resinous composition is contained and used in resinous composition constituting electronic packaging material for electronic device, and includes: a filler ingredient including a crystalline siliceous material with a crystal structure made of at least one member selected from the group consisting of type FAU, type FER, type LTA, type MFI and type CHA, and/or type MWW, wherein: the filler ingredient is free of any activity when evaluated by an “NH3-TPD” method; and includes the crystalline siliceous material in an amount falling in a range allowing the filler ingredient to exhibit a negative thermal expansion coefficient. The filler ingredient may further be free of a surface in which silver, copper, zinc, mercury, tin, lead, bismuth, cadmium, chromium, cobalt and nickel are exposed.