Norman "Lou" Allinger (born c. 1928) is an American computational chemist and Distinguished Research Professor Emeritus of Chemistry at the University of Georgia (UGA) in Athens.
Professor Allinger received his B.S. from the University of California, Berkeley, in 1951 and his Ph.D. from the University of California, Los Angeles, in 1954. He was on the faculty at Wayne State University before coming to the University of Georgia as Research Professor in 1969. He is known for his pioneering efforts in the use of computational chemistry, especially molecular mechanics, to solve a variety of chemical problems. He is the author of the MM2, MM3 and MM4 software packages.
Allinger was elected to the National Academy of Sciences in 1991 and was awarded the Benjamin Franklin Medal in Chemistry in 2002.