Syder may refer to:
Name
As a given name
- Syder Nnodim (fl.1992–1993), Nigerian politician
As a surname
- Branca de Gonta Colaço (1880–1945), Portuguese writer whose full name is Branca Eva de Gonta Syder Ribeiro Colaço
- Daniel Syder (c. 1642/1647–1705), Italian painter
- Jim Syder Jr. (1911–1972), English greyhound trainer
- Jim Syder Sr. (1880–1945), English greyhound trainer and father of Jim Syder Jr.
- Martim Syder (born 1995), Portuguese politician
Places
- Sierre, a municipality in Valais, Switzerland, that was formerly known as Syder