This paper examines the external debt sustainability in Turkey over the period 1970-2010 by using fractionally integrated approach. As a first step, possible structural breaks in the data are not taken into consideration. The findings from Robinson(1994a) test reveal that the process is non-stationary with long memory, therefore, there is no evidence of external debt sustainability in Turkey. In the second step, structural breaks identified by Perron (1998, 2003)