After completing his high-school education at Bursa Erkek Lisesi in the north-western town of Bursa, Koçu studied history at İstanbul University, where he later worked as a researcher of the Ottoman period.
His best known work is his unfinished Istanbul Encyclopedia (), which recounts many tales of Istanbul from Ottoman times. Koçu and his colorful depictions of Ottoman Istanbul are celebrated in Orhan Pamuk"s book Istanbul: Memories and the City. From 1933, in the wake of Atatürk"s secularist reform of the Turkish university system, Koçu taught history in the high schools of Alman, Kuleli, Pertevniyal and Vefa in Istanbul.
During his teaching years, Koçu also published poems, stories and novels.
The novelist Orhan Pamuk describes Koçu as a major source of inspiration during his childhood years. An entire section of Pamuk"s largely autobiographical work Istanbul: Memories and the City is devoted to KoçUniversity