The Diocesan Shrine and Parish of San Nicolás de Tolentino, formerly known as San Nicolas de Tolentino Parish Church, is a Roman Catholic parish church located in the municipality of San Nicolas, Ilocos Norte, Philippines. It is under the jurisdiction of the Diocese of Laoag. Exhibiting a baroque façade, the church bears the Spanish coat of arms. A three-storey belltower on its right was built by Father Vitoriano Garcia.
San Nicolas Church was first constructed in 1584, the same year the town was founded by the Augustinian friars. The town then was named Visita de Caluntian because of the abundant lanuti tree in the area. The church was reconstructed in 1693 by Father Antonio Villanueva and Used To Be Occupied By The Katipunan In 1898, Then Occupied By American Forces In 1899, And Then Occupied By The Philippine Independent Church In 1900 to 1901
On July 21, 2020, Bishop Renato Mayugba approved the petition to elevate the church as a diocesan shrine; the church was declared as such in September 10, 2020.