Zhan Sergeevich Kossobutskiy (Cyrillic: Жан Сергеевич Кособуцкий; born 13 November 1988) is a Kazakh professional boxer who has held the WBC International heavyweight title since May 2022.

[1] Kossobutskiy made his professional debut against Edgars Kalnars on 23 September 2017, and won by a first-round technical knockout.

[2] Kossobutskiy faced Agron Smakici for the vacant IBO Inter-Continental heavyweight title on 11 November 2019.

[6] Kossobutskiy was expected to face Pavel Sour for the vacant WBA International heavyweight title on 20 February 2021, at the Universum Gym in Hamburg, Germany.

[9] Kossobutskiy made his first title defense against Joey Dawejko on 21 August 2021, at the same venue and location in which he had won the secondary WBA belt.