A gas-barrier packaging material includes: 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 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 ± in a range of 1,490 to 1,659 cm -1 and a maximum peak height ² in a range of 1,660 to 1,750 cm -1 as expressed by ±/² is less than one.