[4] She studied costume & design at Mimar Sinan University, and graduated in 2004[5] On 28 July 2011, she married the Turkish actor Onur Saylak in Paris, France.

[8][9] Following appearances in television commercials, Büyüküstün made her television series debut in 2003 on the last four episodes of Sultan Makamı, directed by Aydın Bulut and broadcast on Channel D. Her next period series role was Zarife on Çemberimde Gül Oya, directed by Çağan Irmak, broadcast on Channel D in 2004.

Her next role was the title character in the 2007–2009 television drama Asi, alongside Murat Yıldırım and Çetin Tekindor, directed by Cevdet Mercan.

At the end of 2012, she starred alongside İlker Aksum in the dramatic series 20 Dakika (20 Minutes), a performance that earned her a nomination for the 42nd International Emmy Award for Best Actress.

[10] Büyüküstün, who was appointed as a goodwill ambassador of UNICEF Turkey in 2014,[11] starred alongside Engin Akyürek in the 2014–15 series Kara Para Aşk (Black Money Love).