Gregori Aleksandrovich Margulis (em russo: Григорий Александрович Маргулис; Moscou, 24 de fevereiro de 1946) é um matemático russo.
Margulis foi eleito membro da Academia Nacional de Ciências dos Estados Unidos em 2001.
Recebeu o Prêmio Abel de 2020, juntamente com Hillel Fürstenberg, "por pioneirismo no uso de métodos da probabilidade e dinâmica em teoria dos grupos, teoria dos números e combinatória".
Discrete subgroups of semisimple Lie groups, Ergebnisse der Mathematik und ihrer Grenzgebiete (3) [Results in Mathematics and Related Areas (3)], 17. Springer-Verlag, Berlin, 1991. x+388 pp. ISBN 3-540-12179-X MR1090825
On some aspects of the theory of Anosov systems. With a survey by Richard Sharp: Periodic orbits of hyperbolic flows. Translated from the Russian by Valentina Vladimirovna Szulikowska. Springer Monographs in Mathematics. Springer-Verlag, Berlin, 2004. vi+139 pp. ISBN 3-540-40121-0 MR2035655
Oppenheim conjecture. Fields Medallists' lectures, 272--327, World Sci. Ser. 20th Century Math., 5, World Sci. Publ., River Edge, NJ, 1997 MR1622909
Dynamical and ergodic properties of subgroup actions on homogeneous spaces with applications to number theory. Proceedings of the International Congress of Mathematicians, Vol. I, II (Kyoto, 1990), 193--215, Math. Soc. Japan, Tokyo, 1991 MR1159213
Explicit group-theoretic constructions of combinatorial schemes and their applications in the construction of expanders and concentrators. (Russian) Problemy Peredachi Informatsii 24 (1988), no. 1, 51--60; translation in Problems Inform. Transmission 24 (1988), no. 1, 39--46
Arithmeticity of the irreducible lattices in the semisimple groups of rank greater than 1, Invent. Math. 76 (1984), no. 1, 93--120 MR0739627
Some remarks on invariant means, Monatsh. Math. 90 (1980), no. 3, 233--235 MR0596890
Arithmeticity of nonuniform lattices in weakly noncompact groups. (Russian) Funkcional. Anal. i Prilozen. 9 (1975), no. 1, 35--44
Arithmetic properties of discrete groups, Russian Math. Surveys 29 (1974) 107--165 MR0463353
O'Connor, John J.; Robertson, Edmund F., «Grigory Margulis», MacTutor History of Mathematics archive (em inglês), Universidade de St. Andrews
Grigory Margulis (em inglês) no Mathematics Genealogy Project