A gas-barrier packaging material including: a support; an adhesive layer laminated on the support; a first barrier layer laminated on the adhesive layer; a second barrier layer laminated on the first barrier layer; and a protective layer formed of a coating liquid that contains a polyvalent metal compound, a polyester based resin, and a dispersant that is a sodium salt of a polycarboxylic acid based resin, the protective layer being laminated on the second barrier layer. In the gas-barrier packaging material, the protective layer contains the polyvalent metal compound by about 40 to 90 wt % relative to 100 wt % of the protective layer. When the second barrier layer is separated and an infrared absorption spectrum of the second barrier layer after separation is measured by a transmission method, a ratio between a maximum peak height α in a range of about 1,490 to about 1,659 cm−1 and a maximum peak height β in a range of about 1,660 to about 1,750 cm−1 as expressed by α/β is less than about one.