The present invention relates to a composition for a gel polymer electrolyte, which includes a lithium salt, a non-aqueous organic solvent, a polymerization initiator, and an oligomer containing a polycarbonate-based repeating unit, a gel polymer electrolyte in which mechanical strength and ion transfer capability are improved by polymerization of the composition for a gel polymer electrolyte, and a lithium secondary battery in which external impact and stability during high-temperature storage are improved by including the gel polymer electrolyte.