Antireflection film-attached transparent substrate and image display device

An anti-reflective film-attached transparent substrate comprising:

• a transparent substrate comprising two main surfaces;
• and
• an anti-reflective film on one main surface of the transparent substrate,
• wherein the anti-reflective film has a laminated structure in which at least two layers having different refractive indices are laminated,
• at least one layer among layers in the laminated structure is mainly formed of a Si oxide,
• at least another layer among the layers in the laminated structure is a mixed oxide layer mainly formed of a mixed oxide containing Mo and Nb,
• the mixed oxide layer comprises an oxide of at least one high hardness metal element selected from the group consisting of W, Cr, Mn, Ni, Zr, Ta, and Be,
• a proportion of Mo to a total of Mo and Nb in the mixed oxide layer is 60 at % or less, and
• a proportion of a total of the high hardness metal element to a total of metal elements in the mixed oxide layer is 12 at % or more.