John Mitchell Watt (1 December 1892 – 23 April 1980) was a 20th-century South African physician and pharmacologist.
His family moved to Scotland and he completed his education at Stirling High School.
His proposers were John Phillips, Robert Burns Young, James Harvey Pirie and Sir William Wright Smith.
Rand Afrikaans University awarded him an honorary doctorate (LLD) for his academic writing in 1972.
He was married twice: firstly in 1920 to Yelena Nikonova, secondly in 1942 to Betty Gwendoline Lory.