William Lowrie (18 October 1857 – 20 July 1933) was an Australian agricultural educationist.
Lowrie was the son of John Lowrie, a shepherd, wife Christina, née Anderson. Lowrie was born near Galashiels, Selkirkshire, Scotland. Lowrie was brought up on a farm Clarilaw, one of the largest farms in Roxburghshire, and attended school at Blainslie; he later entered the University of Edinburgh, where he graduated M.A. in 1883, and obtaining a Highland and Agricultural Society's bursary in 1884, studied agriculture and graduated B.Sc. in 1886 with a prize in mathematics and several first-class honours. Lowrie lectured on natural science and agriculture at Gordon's College, Aberdeen.
In 1887 he was appointed Professor at the Roseworthy Agricultural College, South Australia, after the sacking of John D. Custance, and continued his research into the virtues of fallowing and the use of water-soluble phosphates as fertilizer. Following this Lowrie travelled throughout the wheat-growing districts of South Australia, addressing farmers and endeavouring to persuade them to adopt his methods. He resigned his position as principal of Roseworthy Agricultural College after criticism of him in Parliament. He was urged to reconsider by the Agricultural and Horticultural Society and others. W. C. Grasby was appointed as Head Master, freeing Lowrie to concentrate on research and promulgation of modern farming methods and the resignation was withdrawn. He was contracted by the Victorian government to report on the Longerenong and Dookie agricultural colleges. His reports, which were constructive though highly critical, were not welcomed.