Abstract: The present disclosure provides an encapsulating composition, a composition, an encapsulating glue film, an electronic component and a solar cell assembly. The encapsulating composition comprises polyolefin resin, polyethylene glycol dimethacrylate and organic peroxide, and the structural formula of the polyethylene glycol dimethacrylate is represented by a formula (I). When the polyolefin resin is heated and melted, the ethylene glycol dimethacrylate is delaminated and aggregated in the polyolefin resin. A polymer network structure that has a three-dimensional network structure and that has several ester groups and ether bonds is formed in situ in a polyolefin resin matrix, and the polymer network structure may adsorb residual metal ions in the polyolefin resin, thereby reducing the mobility of the metal ions, so as to improve the dry insulation resistance of the polyolefin resin. In addition, said composition has simple components, readily available raw materials and low costs.