Co-Cathedral of Immaculate Conception, Basseterre, Catholic cathedral in Basseterre, Saint Kitts and Nevis.

The Co-Cathedral of Immaculate Conception stands on East Square Street in Basseterre, sharing the seat of the Diocese of Saint John's-Basseterre with the Cathedral of the Holy Family in Saint John's. The present church, designed by Father Claeys, was built from 17 March 1927 and dedicated on 6 December 1928, replacing an earlier Church of the Immaculate Conception. Paving slabs from the old church were carefully removed and reused in the new building.

Jesuits built a church dedicated to Our Lady here during the early French occupation; English soldiers billeted in it burned it down in 1706, and it was rebuilt by 1710 as St. George's, later Anglican. After 1713 Catholics were barred from public worship until an 1829 act removed the disabilities. A church of the Immaculate Conception rose around 1856, was demolished from 1 February 1927, and its replacement, designed by Father Claeys, was dedicated on 6 December 1928 and made co-cathedral in 1981.

The name recalls the Jesuit church of Notre-Dame burnt in 1706; after the 1713 ban on public Catholic worship, families placed domes on their houses to celebrate Mass. Portuguese migrants from Madeira, arriving from 1835, strengthened the congregation. Since 1981 the church has been co-cathedral of the Diocese of Saint John's-Basseterre, sharing the seat with Saint John's.

The cathedral is open for worship and welcomes visitors during services throughout the week. It is respectful to observe silence and dress modestly when entering this religious space.

The 1927 rebuild reused the old church's paving slabs, which were carefully lifted before demolition began on 1 February. The site also held a Formation House for Catholic nuns and a Manse for the priests, so the block covered both worship and the housing of the religious community.