Pierre Jacquinot (born 18.01.1910) is a French physicist and a member of the Paris Academy of Sciences (1966). He was born in Frouard. He graduated from the university in Nancy (1932), and in 1937 received the degree of Doctor of Science at the University of Paris. In 1933—42 he worked at the National Centre for Scientific Research, in 1942 — 46 he was professor at the university in Clermont-Ferrand, in 1962 —69 Director-General of the National Centre for Scientific Research, and from 1969 professor there and director of the Aimé Cotton Laboratory (Orsay); from 1946 he has also been professor at the University of Paris.
His research has concerned optical, interference and atomic spectroscopy, the study of the Zeeman effect and the diffraction of light. In 1939 he discovered a new spectrum of helium. He contributed to Fourier spectroscopy.
In 1958 — 59 he was president of the French Physical Society.