The invention discloses a roller soft package lithium battery sealing device. The device comprises a roller component used for sealing an air bag and a clamping component used for clamping the air bag. The roller component comprises a plurality of upper roller modules and a plurality of lower roller modules, each upper roller module comprises an upper roller, a first electric slip ring, a transmission shaft and a driving mechanism, and a first heating plate is arranged in each upper roller. Each lower roller module comprises a lower roller and a second electric slip ring, and a second heatingplate is arranged in the lower roller. The upper roller corresponds to the lower roller vertically, and the upper roller and the lower roller are attached to a sealing position of a battery air bag. The clamping component clamps two ends of the air bag. The device has advantages that the upper rollers and the lower rollers which are continuously arranged are adopted to heat and pressurize the battery air bag, and hot melting packaging is synchronously achieved in a circulation process; a heating temperature of each roller is relatively independent, and a constant-temperature heating mode or avariable-temperature heating mode can be selected for hot melting packaging.