Donald Sinclair (July 1829 – November 19, 1900) was an Ontario businessman and political figure.

He represented Bruce North in the Legislative Assembly of Ontario as a Liberal member from 1867 to 1883.

[2] Sinclair taught school for several years in Bruce County and near Toronto.

He was elected deputy reeve for Arran township in 1863.

This article about an Ontario Liberal Party MPP is a stub.