To provide a heat-ray shielding film and a method for manufacturing the same, capable of exhibiting excellent optical characteristics and high weather resistance, mainly composed of polyvinyl acetal resin and using composite tungsten oxide fine particles with high heat-ray shielding effect, the method comprising: a first step of obtaining a dispersion liquid by dispersing composite tungsten oxide fine particles expressed by a general formula MyWOz and having a hexagonal crystal structure, and dispersing a dispersant into an organic solvent with a boiling point of 120 deg C. or less; a second step of obtaining a mixture by mixing metal carboxylate into the dispersion liquid obtained by the first step; and a third step of drying the mixture obtained by the second step to thereby obtain a heat-ray shielding fine particle-containing composition, and setting a content of the organic solvent remained in the heat-ray shielding fine particle-containing composition to 5 mass % or less.