Sinclair could refer to:
- Douglas Sinclair, chief engineer of the USS Hastings in the 2260s.
- Sinclair (Lieutenant), served aboard the USS Enterprise in 2267.
- Margaret Sinclair-Alexander, the female commander of the USS Saratoga in the late 2280s.
- Cynthia Sinclair, the wife of Margaret Sinclair-Alexander.
- Sinclair Rowan, captain of the Bluenose IV.