The following dioceses have seminarians in formation at St. John Vianney Theological Seminary:
Archdiocese of Denver Diocese of Bismarck Diocese of Dodge City Diocese of Gallup Diocese of Helena
Archdiocese of Kansas City – Kansas Archdiocese of Oklahoma City Diocese of Phoenix Diocese of Pueblo Diocese of Salina
Diocese of Bui Chu, Vietnam Diocese of Kasana-Luweero, Uganda Diocese of Tarawa and Nauru, Kiribati Archdiocese of Yangon, Myanmar
