She grew up in Istanbul and finished her secondary education in Ankara, where she attended Atatürk High School for Girls.

After Muhsin Ertuğrul suggested, she studied in theatre department of Ankara State Conservatory.

[1] Koçyiğit decided to venture into cinema in 1963 after she was the runner-up in a beauty contest organized by the magazine Ses (literally: Sound).

Lütfü Akad, Atıf Yılmaz, Şerif Gören, Metin Erksan, Orhan Aksoy, Memduh Ün, Ertem Eğilmez, Osman F. Seden, Halit Refiğ are some of the famous directors who have worked with Koçyiğit.

In 2009, she starred in Altın Kızlar the Turkish TV adaptation of the famous American series, The Golden Girls.