William Benjamin Ross (December 12 1855 - January 10 1929) was a Canadian politician, lawyer and businessman.

A lawyer by training, Ross was practiced law in Halifax, Nova Scotia and also pursued business interests such as helping found the Halifax Electric Tramway Company Limited. Ross was appointed to the Canadian Senator as a Conservative in 1912 by Sir Robert Borden. In January 1926 he was appointed Leader of the Opposition in the Canadian Senate by Tory leader Arthur Meighen and served briefly as Government Leader in the Canadian Senate when Meighen formed a short-lived government later that year. After the Conservatives lost the 1926 Canadian election Ross resumed his position as Opposition Leader and remained such until his death.