Leroy Milton Kelly (8 May 1914 – 21 February 2002) was an American mathematician whose research primarily concerned combinatorial geometry. In 1986 he settled a conjecture of Jean-Pierre Serre by proving that n points in complex 3-space, not all lying on a plane, determine an ordinary line--that is, a line containing only two of the n points.
L. M. Kelly received his Ph.D. at the University of Missouri in 1948, advised by Leonard Mascot Blumenthal.