Terms were not announced for the deal, which was disclosed in a tweet by the Twitter engineering team and on the website of the Massachusetts-based Whetlab.
Twitter did not comment on its plan for the service, but artificial intelligence can be used to determine the most relevant tweets and advertising messages for each user, or to better filter spam.
"Over the past year, we have created a technology to make machine learning better and faster for companies, automatically," a statement on the Whetlab website said.
"Twitter is the platform for open communication on the Internet and we believe that Whetlab's technology can have a great impact by accelerating Twitter's internal machine learning efforts."
The move comes with Twitter searching for a new chief executive following Dick Costolo's announcement he is stepping down. Co-founder Jack Dorsey will be the interim CEO.
Whetlab, which was founded by computer scientists and neuroscientists from Harvard and Canadian universities, aims to help companies make better use of artificial intelligence, or machine learning.
With some 300 million active users, Twitter has been growing at a slower pace than some rival social networks and has yet to show a profit, despite creating new advertising products for the one-to-many messaging service.
Facebook has been investing heavily in artificial intelligence to show more relevant items in user news feeds.