TV Line reports that the actress will play Sarah, a new love interest for the womanising Barney (Neil Patrick Harris).
Boniadi is best known for her role as Leyla Mir on ABC soap opera General Hospital and has also made guest appearances on 24 and Hawthorne. Her film credits include roles in Iron Man, Charlie Wilson's War and new Russell Crowe thriller The Next Three Days.
It was recently announced that John Lithgow is in talks to appear on How I Met Your Mother as Barney's long-lost father.
The series airs on Mondays at 8/7c on CBS.