The work aims to increase the bonding strength of zirconium alloy film-based interface by SnAl elements in Cr film and intermediate-temperature liquid phase sintering. SnAl element was added to Cr target to prepare a CrSnAl alloy target with an evenly distributed atomic ratio of Cr∶Sn∶Al=95∶4∶1. DC magnetron sputtering (DCMS) technology was used to prepare approximately 5 μm thick CrSnAl film on the surface of zirconium alloy and then the CrSnAl film sample was placed in an Ar atmosphere furnace for sintering at an intermediate temperature of 600 ℃ for 30 minutes and the coated sample was cooled down to room temperature with the furnace. Effect of intermediate-temperature sintering on morphology, structure and element diffusion of CrSnAl films was investigated by XRD, SEM, EDS and stereoscopic microscope, respectively and the film-based interface bonding strength was evaluated by coating bending fracture morphology, cutting scratch force and chip morphology. The defects such as pores on the surface of Cr film with SnAl addition were significantly reduced, and the bond strength at the interface of the film was greatly improved. The average bonding strength at the interface was increased from 41.7 MPa to 45.8 MPa. The toughness of the CrSnAl film after sintered at 600 ℃ was enhanced, and the dimple appearance was observed. The shear lip was only 1/2 of the pre-sintered CrSnAl film, and the CrSnAl/Zr interface bond strength was further increased to 52.1 MPa. Therefore, the addition of SnAl to the Cr film is beneficial to the diffusion of element at the interface of the film, and has a great influence on the bonding strength of the film-based interface. CrSnAl film sintered at medium temperature increases the toughness of the film and the bonding strength of the film-based interface, thus improving the interface properties of the film-based interface.