There is provided a strip casting method using a twin roll strip casting process in which molten steel is supplied through an injection nozzle to a region between twin rolls rotating in opposite directions to produce a strip having a predetermined thickness and a high degree of edge quality. The twin roll strip casting method includes: performing the casting process by setting a casting thickness to have a minimal value during an early stage of the casting process in which edge bulging occurs; and performing the casting process by increasing the casting thickness to a maximum value after the molten steel reaches a pre-set target temperature as the casting process proceeds.