Sayyid Shahabeddin Hosseini Tonekaboni (Persian: سیّد شهاب‌الدین حسینی تنکابنی; born February 3, 1974) is an Iranian actor, producer, director and screenwriter.

He is known for his collaborations with Iranian Academy Award-winning director Asghar Farhadi in About Elly (2009), A Separation (2011), and The Salesman (2016).

He dropped out of the University of Tehran as a psychology student and emigrated to Canada.

[2] Hosseini has won the Silver Bear for Best Actor for A Separation at the 61st Berlin International Film Festival, and the Best Actor Award at the 2016 Cannes Film Festival for his role in The Salesman.

[5] In 2020, Hosseini co-founded Pol Media ("pol" translating to "bridge" in Persian) with director Kourosh Ahari and producer Alex Bretow, a distribution and production company aiming to "bridge the gap" between Iranian art, culture and cinema with that of the U.S.[6]