The present invention relates to a wireless communication system and, specifically, to a method and an apparatus therefor, the method comprising the steps of: receiving scheduling information for a plurality of consecutive transmission time intervals (TTIs) and transmitting data on the basis of the scheduling information, wherein the scheduling information includes a combination of a first symbol index and the number of consecutive symbols, the data is transmitted from a starting symbol of a first TTI (starting TTI) among the plurality of consecutive TTIs to an ending symbol of the last TTI on the basis of the scheduling information, and the index of the starting symbol and the index of the ending symbol are determined on the basis of the combination of the first symbol index and the number of the consecutive symbols.