St. Moritz ( SAN mə-RITS, US also SAYNT -⁠, UK also sənt MORR-its; German, in full: Sankt Moritz [zaŋkt moˈrɪts, ˈmoːrɪts] locally [saŋkt]; Romansh: San Murezzan [sam muˈʁetsən] ; Italian: San Maurizio; French: Saint-Moritz) is a high Alpine resort town in the Engadine in Switzerland, at an elevation of about 1,800 metres (5,910 ft) above sea level. It is Upper Engadine's major town and a municipality in the administrative region of Maloja in the Swiss canton of the Grisons.

St. Moritz lies on the southern slopes of the Albula Alps below the Piz Nair (3,056 m or 10,026 ft) overlooking the flat and wide glaciated valley of the Upper Engadine and eponymous lake: Lake St. Moritz.