Cerebrospinal fluid (CSF) leakage caused by accidents or diseases resulting from traumatic brain injury, inflammation, tumor erosion and surgery can lead to many complications. In this study, a multifunctional composite double-layer hydrogel was designed by simulating the structure of native dura mater, which was composed of polyacrylic acid (PAA), polyethyleneimine (PEI), sodium alginate (SA), β-cyclodextrin (β-CD) and edaravone (Ed). The PAA/PEI layer had strong wet adhesion characteristics, while the PEI/SA@β-CD/Ed layer exhibited significant antioxidant, drug release and biocompatibility properties. By controlling the concentration of Ca