A laminate including a first base material layer, a second base material layer, and a sealant layer in this order, wherein all three layers include a polyolefin film; the polyolefin film of the first base material layer or the second base material layer includes an inorganic oxide layer on at least one surface thereof; and each of the first base material layer, the second base material layer, and the sealant layer has a heat shrinkage rate, in a travel direction after heating at 120° C. for 15 minutes, which satisfies the following inequalities: heat shrinkage rate of the second base material layer≤5% (Inequality 1); heat shrinkage rate of the second base material layer≥heat shrinkage rate of the first base material layer (Inequality 2); and, heat shrinkage rate of the second base material layer≥heat shrinkage rate of the sealant layer (Inequality 3). ws