Hector Macpherson Sr. was born in Ontario, Canada, on April 22, 1875. After studying in Canada, England, and Germany, Macpherson settled in Oregon in 1911 and taught economics and sociology at the Oregon Agricultural College (later Oregon State University) in Corvallis for 15 years until 1926. During his tenure as professor, Macpherson was involved in a number of national and state commissions that examined rural credit and cooperative marketing systems.

Macpherson was active in advocating for administrative reorganization of Oregon's state political structure. In 1926, he successfully ran for representative of Linn County, serving in the 1927 Oregon legislative session. He subsequently served in the 1929, 1931, and 1939 sessions. As a representative, Macpherson was a member of the Joint Committee on Administration Reorganization in 1929-1930. In 1930, he co-sponsored the Zorn-Macpherson School Moving Bill, which, among other things, proposed consolidating the University of Oregon and Oregon State College (later Oregon State University); the bill was defeated by a proportion of more than 6 to 1.

Macpherson married Margaret Buchanan Dupree in 1911. The couple had three children: David, Miriam, and Hector, Jr. Hector Macpherson died in March 1970.