William Milo Olin (September 18, 1845 – April 15, 1911) was an American journalist and politician who served as the Massachusetts Secretary of the Commonwealth.

In the fourteen years[1] Olin worked for the Advertiser[1] he was, in succession, a reporter, editor and Washington, D.C. correspondent of that newspaper.

[1] He was later a private secretary to Massachusetts Governors Thomas Talbot and John Davis Long and U.S.

[2] A Republican,[3] he served as Massachusetts Secretary of the Commonwealth from 1892 until he died in Boston on April 15, 1911.

[2] At the time of his death, he was chief of staff of the National Grand Army of the Republic.