Atlantis project MeyGen, located in the stretch of water between Caithness and Orkney, has provided enough energy during August to power 2,000 Scottish homes.
The first phase of the project will involve three turbines with the third expected to come into use in September.
In a production update, the company said the power station had created more than 700 MWh of electricity in August.
David Taaffe, director of project delivery at MeyGen said: “The production performance from the installed turbines on the MeyGen project has been very good.
“August proved to be a world record month, providing enough energy to power 2,000 Scottish homes from just two turbines.
“With yet another successful installation campaign expertly completed this week by the Atlantis operations team, we expect to continue to break records throughout the rest of the year generating both predictable power and revenue.”
Dr Sam Gardner, acting director of WWF Scotland said the world record for monthly production was a “really exciting moment”.
He said: “This is a sign that Scotland is really making progress in harnessing the power of our seas and that we’re on our way to securing a low carbon future.
“By supporting projects like this one, which provide clean, predictable, homegrown power, the Scottish Government can help fight climate change, strengthen our energy security and drive further job creation in sustainable industries.”