The 2018 İstanbul Cup (also known as the TEB BNP Paribas İstanbul Cup for sponsorship reasons) was a tennis tournament played on outdoor clay courts.

It was the 11th edition of the İstanbul Cup, and part of the WTA International tournaments of the 2018 WTA Tour.

It took place in Istanbul, Turkey, from 23 through 29 April 2018.

The following players received wildcards into the singles main draw: The following players received entry from the qualifying draw: The following pairs received wildcards into the doubles main draw: