The Dârjiu fortified church (Romanian: Biserica fortificată din Dârjiu; Hungarian: Székelyderzsi erődtemplom) is a Unitarian fortified church in Dârjiu (Székelyderzs), Harghita County, in the Transylvania region of Romania. It was built by the Székely Hungarian community at a time when the area belonged to the Kingdom of Hungary. Initially Roman Catholic, it became Unitarian following the Reformation. The church is noted for its interior frescoes, and together with the surrounding village, forms part of the villages with fortified churches in Transylvania UNESCO World Heritage Site.