During the construction of double-layer porous asphalt pavement， a binder layer needs to be laid to ensure that the upper and lower layers are bonded by enough binding force to resist potential pavement diseases during service. To investigate the dosage range and force characteristics of the binder layer of double-layer porous asphalt pavement， this paper utilized the pressure film and pavement texture scanner to obtain the interlayer contact characteristics of both single-layer and double-layer porous asphalt pavement， thereby determining the recommended dosage of the binder layer for the double-layer pavement； and the oblique shear test was conducted to obtain the failure characteristics of the binder layers in both single-layer and double-layer porous asphalt pavement. The results indicate that the interlayer contact area of the double-layer porous asphalt pavement is larger， which is approximately 1.5 times that of the single-layer porous asphalt pavement. The OGFC mix used in the lower layer of the double-layer porous asphalt pavement exhibits more microscopic concave and convex structures and a larger surface area， which is about 1.18~1.20 times that of the AC mix. Based on the surface area multiplier relationship and the standard recommended value， it is recommended that the dosage of the binder layer for double-layer porous asphalt pavement be 0.8~1.2 L/m2. The shear resistance of the binder layer in double-layer porous asphalt pavement is superior to that in single-layer porous asphalt pavement. The interlayer shear strength of single-layer porous asphalt pavement is solely provided by the bonding force of the binder layer. The interlayer shear strength of double-layer porous asphalt pavement is provided by the bonding force of the binder layer and the interlocking of interlayer particles. After reaching the maximum shear force， the interlayer particles continue to resist shear deformation， and the shear resistance does not decline abruptly.