A photomask blank comprises a transparent substrate, a light-shielding film of an optionally transition metal-containing silicon material, and an etching mask film of a chromium compound base material. The etching mask film consists of multiple layers of different composition which are deposited by reactive sputtering, the multiple layers including, in combination, a first layer of a material which imparts a compression stress when deposited on the substrate as a single composition layer and a second layer of a material which imparts a tensile stress when deposited on the substrate as a single composition layer.