The Diocese of Tui-Vigo (Latin: Dioecesis Tudensis-Vicensis) is a Latin Church ecclesiastical territory or diocese of the Catholic Church in Northwestern Spain.

It is a suffragan diocese in the ecclesiastical province of the metropolitan Archdiocese of Santiago de Compostela.

[1] Its cathedral is Tui Cathedral, dedicated to Santa Maria, in the episcopal see of Tui.

It also has a co-cathedral, dedicated to Saint Martin and the Virgin Mary in Vigo: the Co-Cathedral of Santa María, Vigo.

As of 2014[update], it pastorally served 533,800 Catholics (94.9% of 562,200 total) on 1,718 km2 in 275 parishes and 60 missions with 254 priests (195 diocesan, 59 religious), 2 deacons, 472 lay religious (102 brothers, 370 sisters) and 14 seminarians.