The Diocese of Subotica is a Latin diocese of the Catholic Church in Serbia. It is subject to the Roman Catholic Archdiocese of Belgrade. The Diocese is centered in the city of Subotica.

Subotica is a city and the administrative center of the North Bačka District in the autonomous province of Vojvodina, Serbia. Formerly the largest city of Vojvodina region, contemporary Subotica is now the second largest city in the province, following the city of Novi Sad. According to the 2022 census, the city itself has a population of 94,228, and the population of metro area stands at 123,952 people.