A gas barrier packaging material precursor, comprising: a support; an adhesion layer provided on one surface of the support; and a barrier layer and a protective layer formed adjacent to each other on the adhesion layer, wherein said precursor has a laminated structure in which the adhesion layer, the barrier layer and the protective layer are formed in this order on the surface, alternatively the adhesion layer, the protective layer and the barrier layer are formed in this order on the surface, wherein: the adhesion layer contains a composite of a silicon compound having any one of an isocyanate group, an amino group, and a mercapto group, or a hydrolysate of the compound, an acrylic polyol, and an isocyanate compound; the barrier layer comprises a polycarboxylic acid polymer and at least one silicon compound selected from the group consisting of a silane coupling agent represented by a general formula Si 3 Z, a hydrolysate thereof, and a condensate of these materials, wherein R denotes an alkyl group having 1 to 6 carbon atoms, Z denotes an organic group containing a glycidyloxy group or an amino group, and each R may be the same or different from one another; the protective layer is formed of a coating liquid containing a polyvalent metal compound, a polyester resin, and a dispersant, wherein the protective layer contains the polyvalent metal compound by 40 to 90 mass% relative to 100 mass% of the protective layer; and when the barrier layer is separated from the gas barrier packaging material precursor to measure an infrared absorption spectrum of the barrier layer by a transmission method, a ratio (α/β) of a maximum peak height (α) of absorbance in a range of 1490 to 1659 cm -1 to a maximum peak height (β) of absorbance in a range of 1660 to 1750 cm -1 is less than 1, wherein the acrylic polyol has a hydroxyl value in a range of 5 to 200 KOH mg/g and the silicon compound is a silane coupling agent, wherein the formulation ratio of the acrylic polyol and the silane coupling agent is 1/1 to 1000/1 by mass ratio. a support; an adhesion layer provided on one surface of the support; and a barrier layer and a protective layer formed adjacent to each other on the adhesion layer, wherein said precursor has a laminated structure in which the adhesion layer, the barrier layer and the protective layer are formed in this order on the surface, alternatively the adhesion layer, the protective layer and the barrier layer are formed in this order on the surface, wherein: the adhesion layer contains a composite of a silicon compound having any one of an isocyanate group, an amino group, and a mercapto group, or a hydrolysate of the compound, an acrylic polyol, and an isocyanate compound; the barrier layer comprises a polycarboxylic acid polymer and at least one silicon compound selected from the group consisting of a silane coupling agent represented by a general formula Si 3 Z, a hydrolysate thereof, and a condensate of these materials, wherein R denotes an alkyl group having 1 to 6 carbon atoms, Z denotes an organic group containing a glycidyloxy group or an amino group, and each R may be the same or different from one another; the protective layer is formed of a coating liquid containing a polyvalent metal compound, a polyester resin, and a dispersant, wherein the protective layer contains the polyvalent metal compound by 40 to 90 mass% relative to 100 mass% of the protective layer; and when the barrier layer is separated from the gas barrier packaging material precursor to measure an infrared absorption spectrum of the barrier layer by a transmission method, a ratio (α/β) of a maximum peak height (α) of absorbance in a range of 1490 to 1659 cm -1 to a maximum peak height (β) of absorbance in a range of 1660 to 1750 cm -1 is less than 1, the adhesion layer contains a composite of a silicon compound having any one of an isocyanate group, an amino group, and a mercapto group, or a hydrolysate of the compound, an acrylic polyol, and an isocyanate compound; the barrier layer comprises a polycarboxylic acid polymer and at least one silicon compound selected from the group consisting of a silane coupling agent represented by a general formula Si 3 Z, a hydrolysate thereof, and a condensate of these materials, wherein R denotes an alkyl group having 1 to 6 carbon atoms, Z denotes an organic group containing a glycidyloxy group or an amino group, and each R may be the same or different from one another; the protective layer is formed of a coating liquid containing a polyvalent metal compound, a polyester resin, and a dispersant, wherein the protective layer contains the polyvalent metal compound by 40 to 90 mass% relative to 100 mass% of the protective layer; and when the barrier layer is separated from the gas barrier packaging material precursor to measure an infrared absorption spectrum of the barrier layer by a transmission method, a ratio (α/β) of a maximum peak height (α) of absorbance in a range of 1490 to 1659 cm -1 to a maximum peak height (β) of absorbance in a range of 1660 to 1750 cm -1 is less than 1, wherein the acrylic polyol has a hydroxyl value in a range of 5 to 200 KOH mg/g and the silicon compound is a silane coupling agent, wherein the formulation ratio of the acrylic polyol and the silane coupling agent is 1/1 to 1000/1 by mass ratio.