St. Catherine or St. Katherine may refer to a number of saints named Catherine, or:
Geography
Canada
St. Catharines, a city in Ontario
St. Catharines (federal electoral district), federal
St. Catharines (provincial electoral district), in Ontario
Sainte-Catherine, Quebec, a city in Quebec
United Kingdom
St Catherine, Somerset, a village and civil parish in Somerset, England
St Catherine's, Lincoln, an area of Lincoln, Lincolnshire, England
St Catherine's Hill, Dorset, a hill in Dorset, England
St. Catherine's Hill, Hampshire, a chalk hill in Hampshire, England
St Catherine's Hill, Surrey, a sandstone hill in Surrey, England
St. Catherine's Down, a chalk down on the Isle of Wight, England
St Catherine's Point, the southernmost point on the Isle of Wight, England
St. Catherine's Valley, a valley in South Gloucestershire, England
St Catherines, Argyll, a village in Argyll and Bute, Scotland
St Catherine's Island, Pembrokeshire, Wales
St Katharine's by the Tower, a religious precinct in London (1147–1825)
St Katharine Docks, a former dock and now a mixed-use district in central London
United States
St. Catherine, Florida, an unincorporated community
Saint Catharine, Kentucky, an unincorporated community
St. Catharine, Missouri, an unincorporated community
St. Catherines Island, on the coast of Georgia
St. Katherine's Historic District, in Davenport, Iowa
Lake St. Catherine (Louisiana), a lake in New Orleans, Louisiana
Elsewhere
Saint Catherine, Egypt, a city in the South Sinai Governorate, Egypt
Saint Catherine Parish, a parish in Middlesex, Jamaica
Hospitals
St Catherine's Health Centre, in Birkenhead, Merseyside, England
St Catherine's Hospital, Doncaster, in Doncaster, South Yorkshire, England
St. Catherine's Hospital, Rochester a 1315 leper hospital in Rochester, Kent
Monasteries and convents
Saint Catherine's Monastery, a monastery in Saint Catherine, Egypt
St Catharine's Convent, Augsburg, Germany
St Catharine's Convent, Edinburgh, Scotland
St. Catherine of Sienna Convent, a convent in Springfield, Kentucky
St. Catherine's Priory, Lincoln, a priory in Lincolnshire, England
St. Catherine's Priory, Ribe, a Dominican priory in Denmark
St. Catherine's Priory, Roskilde, a Dominican priory in Denmark
St. Katherine's Abbey, Monisternagalliaghduff, an Augustinian nunnery in County Limerick, Ireland
Schools
St Catherine's School (disambiguation), many schools, colleges and universities
St Catharine's College, Cambridge, a college of Cambridge University
St Catherine's College, Oxford, a college of Oxford University
St Katherine's School, a secondary school in Somerset, England
St. Katherine College, a four-year undergraduate college in Encinitas, California
Other
St. Catherine (album), a 2015 album by the band Ducktails
MV St Catherine, a 1983 ferry, crossing Portsmouth to Fishbourne, Isle of Wight, England
St. Catharine (Waldorf, Maryland) or Dr. Samuel A. Mudd House, a historic house in Maryland
St Catherine's Castle, a small device fort in Cornwall, England
St Catherine's Court, a Tudor manor house in north of Bath, England
St Catherine's Fort, a Palmerston fort
St. Catherine International Airport, in Saint Catherine, Egypt
St. Catherine's Day or Kadripäev, a celebration in Estonia
Feast of Saint Catherine, a religious and civil celebration annually held in Italy and other locations
Order of Saint Catherine, an award of Imperial Russia