The actress - who played Raj's sister Priya on the CBS sitcom - has been cast as a law student, according to The Hollywood Reporter.
She will appear in the Suits winter premiere later this year - the show's summer finale airs on August 23 on USA.
Her character Maria is a recent graduate from Harvard Law and attracts the attention of a number of top law firms, but Louis (Rick Hoffman) is determined to recruit her as his associate.
Mann - born Aarti Majumdar - has previously appeared in episodes of Heroes and CBS soap The Young and the Restless.
Suits airs on Thursdays at 10pm on USA. In the UK, the series is broadcast on Dave.
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Watch a promo for the next episode of Suits below: