To obtain a calcium silicate molding having high strength while excellent in moisture controlling performance and moisture absorbing/releasing capability accompanied by less dimensional change.

This calcium silicate molding is produced by autoclaving a molding from a slurry raw material comprising a silicious raw material, a lime raw material and a reinforcing fiber, wherein the silicious raw material contains 40 wt.% or more diatomaceous earth and the total raw material contains 15 wt.% to 80 wt.% of the diatomaceous earth.