One embodiment of the present invention relates to a method by which a terminal performs observed time difference of arrival (OTDOA)-related operations in a wireless communication system, the method comprising the steps of: receiving a ProvideAssistanceData message from a server; receiving a RequestLocationInformation message from the server; measuring a reference signal time difference (RSTD) on the basis of a reference cell after receiving the RequestLocationInformation message; and transmitting the RSTD measurement result to the server, wherein the reference cell is a reference cell indicated by information included in the ProvideAssistanceData or is selected by the terminal from among a plurality of cells indicated by the information included in the ProvideAssistanceData.