Bill Crothers (William Frederick Crothers; born December 24, 1940 in Markham, Ontario) is a retired Canadian athlete.
At one point, Crothers held the Canadian record in all distances from 400 metres to 1500 metres and was holder of the world 800 metres indoor record. In 1963, he ran the two fastest 800 metres races of the year. He was named Lou Marsh Trophy winner as Canada's top athlete of 1963. Crothers competed for Canada in the 1964 Summer Olympics held in Tokyo, winning a silver medal in the 800 metres. He also competed in the 400 metres, but was eliminated in the semi-finals. He received the Lionel Conacher Award as Canada's top male athlete of 1964. Crothers was ranked by Track & Field News as the top 800 metres runner of 1965 and the second best of the decade.
He has been inducted into the Canadian Olympic Hall of Fame (1965), the Canada's Sports Hall of Fame (1971), and the Ontario Sports Hall of Fame (1997).
Crothers was a pharmacist in the Markham area for many years, and is a trustee (and past Board Chair) for the York Region District School Board. Bill Crothers Secondary School, an athletic-focused secondary school in York Region opened in his honour in August 2008.