Starting her professional career at the very early age of 15, she studied in theatre department of Pera Fine Arts High School.
Sözen starred in many Turkish TV hits including Çemberimde Gül Oya, Bıçak Sırtı, Bir Bulut Olsam, Muhteşem Yüzyıl, "Kırmızı Oda" and Şubat.
Sözen attracted international attention with her phenomenal acting in Nuri Bilge Ceylan's Palme d'Or winning Kış Uykusu in 2014.
Following her role in the 3rd Season of Éric Rochant's influential series Le bureau des légendes in 2017, Sözen moved to Paris for a while and worked on her French.
[8] As of 2014, she is in a relationship with Harun Tekin who is one of the founding members and the vocalist of the Turkish rock band Mor ve Ötesi.