The embodiments of the present disclosure disclose a battery heating system and method, and relate to the field of batteries. The battery heating system may include: a temperature sampling module configured to collect a target sampling temperature; a control module configured to control a heating module to enter a first heating mode when the target sampling temperature is not lower than a preset expected heating temperature; the heating module configured to enter the first heating mode to intermittently heat the battery module set by using a first portion of external electric energy, so as to maintain the target sampling temperature at the preset expected heating temperature.