The Diocese of Wrexham (Latin: Dioecesis Gurecsamiensis) is a Latin Church ecclesiastical territory or diocese of the Catholic Church in Wales. The diocese is a suffragan in the ecclesiastical province of the metropolitan Archdiocese of Cardiff-Menevia.

The diocese was erected on 12 February 1987 from the Diocese of Menevia. Before 1916 this territory was part of the Roman Catholic Diocese of Shrewsbury. The current bishop is The Right Reverend Peter Brignall, the 3rd Bishop of Wrexham. On 27 June 2012, Pope Benedict XVI appointed the then Monsignor Brignall, who was at that time the Diocese of Wrexham's Vicar General, to succeed the retiring bishop, Edwin Regan. Bishop Peter's episcopal ordination took place on 12 September 2012 in Wrexham Cathedral.

The diocese covers an area of 8,361 km² of the ancient counties of Anglesey, Caernarfonshire, Denbighshire, Flintshire, Merionethshire and Montgomeryshire (the local government areas of Conwy, Anglesey, Denbighshire and Flintshire, Gwynedd, Wrexham and the former Montgomeryshire).

The see is in the city of Wrexham where the seat is located at the Cathedral Church of Our Lady of Sorrows.

(Any dates appearing in italics indicate de facto continuation of office. The start date of tenure below is the date of appointment or succession. Where known, the date of installation and ordination as bishop are listed in the notes together with the post held prior to appointment.)

There are a total of six deaneries in the Diocese of Wrexham, all of which cover several churches in that area, overseen by a dean.

The deaneries include:

52°55′N 3°34′W / 52.92°N 3.57°W / 52.92; -3.57