Sepp is a surname. When borne by Estonian-descended people, it is usually derived from sepp meaning "smith".

Notable people with this surname include:

• The Sepp publishing family, four generations of printers and artists active in Amsterdam between 1768 and 1860
• Adeele Sepp (born 1989), Estonian actress
• Andre Sepp (born 1971), Estonian politician
• Anna Maria Sepp (born 1996), Estonian sailor
• Boris Sepp (1894–1941), Estonian lawyer and politician
• Dennis Sepp (born 1973), Dutch footballer
• Evelyn Sepp (born 1972), Estonian sports figure and politician
• Heino Sepp (1936–2008), Estonian rally driver
• Jan Sepp (1778–1853), Dutch entomologist and artist
• Johan Sepp (1884–1953), Estonian politician
• Johann Nepomuk Sepp (1816–1909), German historian and politician
• Kalev Sepp, Estonian-American defense analyst
• Kätlin Sepp (born 1992), Estonian swimmer
• Kurt Sepp (born 1935), German ice hockey player
• Leo Sepp (1892–1941), Estonian financial figure, writer and politician
• Olav Sepp (born 1969), Estonian chess champion
• Ott Sepp (born 1982), Estonian actor
• Sigrid Sepp (born 1998), Estonian swimmer
• Tõnu Sepp (born 1946), Estonian music teacher
• Uudo Sepp (born 1997), Estonian singer

See also

• Seppä, a Finnish surname with the same meaning (smith).
• Sepp (given name)