St Martin's Church (Dutch: Sint-Maartenskerk), also called St Martin's Cathedral (Dutch: Sint-Maartenskathedraal), is a church and former cathedral in the Belgian city of Ypres.

With this, Saint Martin's Church was elevated to cathedral status, as it became the see of the new diocese.

In 1656 the secular and religious authorities of the then Spanish Netherlands destroyed the monument to Bishop Cornelius Jansen in St Martin's Cathedral - a symbolic act as part of the increasing persecution of Jansen's disciples, the Jansenists.

As noted by Jonathan Israel[3] many of the Ypres citizens were angry and distressed at this demolition.

After the Concordat of 1801 between Napoleon and Pope Pius VII, Ypres was incorporated into the diocese of Ghent, and Saint Martin's lost its status as a cathedral.