Margaret Sinclair

Margaret Sinclair may refer to:


 * Margaret Sinclair (nun) (1900–1925), Scottish Roman Catholic nun
 * Margaret P. Sinclair (1950–2012), Canadian mathematics educator
 * The maiden name of Margaret Trudeau
 * Margaret Sinclair, Countess of Caithness, see William Sinclair, 2nd Earl of Caithness
 * Margaret Sinclair Ogden on List of Guggenheim Fellowships awarded in 1960