John Michael Harrison (born 1944) is an American researcher, known for his contributions to the theory of operations research, in particular stochastic networks and financial engineering. He has authored two books and nearly 90 journal articles. He obtained a B.S. in industrial engineering from Lehigh University (1966), a M.S. from Stanford University (1967), and a Ph.D. in operations research (1970) also from Stanford University. In 2008, Harrison was elected a member of the National Academy of Engineering for fundamental contributions to stochastic networks and financial engineering.