Mar Thoma Sleeha Cathedral is a Syro-Malabar Catholic cathedral located in Bellwood, Illinois, United States. It is the seat for the St. Thomas Syro-Malabar Catholic Eparchy of Chicago. The church was dedicated on July 5, 2008, by Cardinal Mar Varkey Vithaythil. The grotto on the cathedral grounds was dedicated by Major Archbishop George Alencherry in October 2011.