The 2018 St. Petersburg Open was a tennis tournament played on indoor hard courts.

It was the 23rd edition of the St. Petersburg Open, and part of the ATP World Tour 250 Series of the 2018 ATP World Tour.

It took place at the Sibur Arena in Saint Petersburg, Russia, from September 17 through 23, 2018.

[1] The following players received wildcards into the singles main draw: The following players received entry from the qualifying draw: The following player received entry as a lucky loser: The following pairs received wildcards into the doubles main draw: