The Diocese of Isiolo is a Latin Church ecclesiastical territory or diocese of the Catholic Church in the Eastern Province, Kenya.
Its episcopal see is in Isiolo, where the St. Eusebius Cathedral is located.
The Apostolic Vicariate of Isiolo (Vicariatus Apostolicus Isiolansus) was created on 15 December 1995 on territory split off from the Diocese of Meru in Eastern Province, Kenya.
On February 15, 2023, Pope Francis elevated the vicariate to the Diocese of Isiolo and appointed Anthony Ireri Mukobo as its first bishop.[1]
As per 2014, the vicariate pastorally serves 49,800 Catholics (34.8% of 143,294 total) on an area of 25,605 km², in 13 parishes and a mission with 22 priests (16 diocesan, 6 religious), 55 lay religious (9 brothers, 46 sisters) and 12 seminarians.