2018 Istanbul Open
The 2018 Istanbul Open was a men's tennis tournament played on outdoor clay courts. It was the fourth edition of the Istanbul Open, and an ATP World Tour 250 event. It took place at the Koza World of Sports Arena in Istanbul, Turkey, from 30 April-6 May 2018.Seeds
- Rankings are as of April 23, 2018.
Other entrants
The following players received wildcards into the main draw:
The following players received entry from the qualifying draw:
;Before the tournament
Seeds
- Rankings are as of April 23, 2018.
Other entrants
The following pairs received wildcards into the doubles main draw:
;During the tournament
Singles
