The 2018 Swiss Open Gstaad (also known as the 2018 J. Safra Sarasin Swiss Open Gstaad for sponsorship reasons) was a men's tennis tournament played on outdoor clay courts.

It was the 51st edition of the Swiss Open, and part of the ATP World Tour 250 Series of the 2018 ATP World Tour.

It took place at the Roy Emerson Arena in Gstaad, Switzerland, from 23 July through 29 July 2018.

[1] The following players received wildcards into the main draw: The following players received entry from the qualifying draw: The following players received entry as lucky losers: The following pairs received wildcards into the doubles main draw: The following pair received entry as alternates: