William Duthie Kinnear (3 December 1880 – 5 March 1974) was a Scottish rower who competed for Great Britain at the 1912 Summer Olympics and won major single scull events prior to the First World War.

He first joined the Cavendish Rowing Club and in 1903 won the West End ARA sculling championship.

[2] Kinnear then joined the Kensington Rowing Club and won many sculling championships on the River Thames over the next few years.

[3] Kinnear won the gold medal in the single sculls, rowing at the 1912 Summer Olympics in Stockholm.

During World War I Kinnear served with the Royal Naval Air Service and then became a rowing coach.