Provided are a method for a user equipment (UE) to perform early data transmission (EDT) in a wireless communication, and an apparatus supporting the same. The method may include: receiving system information including a threshold for the EDT; determining whether or not a condition for initiating the EDT is satisfied, by comparing the threshold for the EDT with a size of data for transmission; if the condition is satisfied, performing the EDT; and if the condition is not satisfied, performing a radio resource control (RRC) connection establishment or resume procedure.