A method and apparatus for determining a positioning measurement interval in a wireless communication system are disclosed. The method includes acquiring a message including Observed Time Difference of Arrival (OTDOA) related data in a higher layer, wherein the OTDOA related data includes a plurality of cell identifiers and Positioning Reference Signal (PRS) configuration information of corresponding cells, transmitting the ODTOA related data to a physical layer from the higher layer, and determining the RSTD measurement interval by the following Equation by using a plurality of cell-specific PRS periods obtained using the PRS configuration information in the physical layer: TRSTD=TPRS·(M−1)+Δ where TRSTD denotes the length of the RSTD measurement interval, TPRS denotes the largest of the plurality of cell-specific PRS periods, M denotes the number of PRS positioning occasions, and Δ denotes a measurement time for one PRS positioning occasion.