Steward attended Oregon Agricultural College in 1917-1918 and 1919-1920 and earned a BS in Agriculture in 1921. In 1921, he became a faculty member in botany at the University of Nanking in Nanking, China. He and his wife, Celia Belle Speak Steward, were appointed as educational missionaries by the Methodist Board of Missions. He returned to the United States for several years in the late 1920s to complete AM and PhD degrees in biology at Harvard University. Steward spent most of the 1930s and 1940s in China and was interned at Chapei Camp in Shanghai from 1943 to 1945. He returned to the United States permanently in 1950. Albert N. Steward was appointed by Oregon State College as Associate Professor of Botany, Herbarium Curator, and Associate Botanist for the Agricultural Experiment Station in 1951. He held these positions until his death in 1959.
