Hayal Köseoğlu (born 20 December 1992) is a Turkish actress and singer, known for her roles Açelya in Mucize Doktor and Sasha Doğan in Mahkum.

Hayal Köseoğlu was born on December 20, 1992, in Istanbul. She completed her education at Istanbul Aydın University, Faculty of Fine Arts, Department of Drama and Acting. Köseoğlu, who met acting at a young age, had her first acting experience in the fantasy comedy series Ruhsar series broadcast on Kanal D at the age of 6 and hit series Mahallenin Muhtarları. She also appeared in the TV series Aşk-ı Memnu, Muhteşem Yüzyıl, İstanbullu Gelin. She had leading role in youth series Arkadaşlar İyidir.

She played as Derya in Ufak Tefek Cinayetler. She was cast in medical series Mucize Doktor. As of 2022, she played Sasha in Fox's Mahkum. She played in Gain web series Cezailer about Rosenhan experiment.^[1]