Wen-Ch'ing (Winnie) Li (Chinese: 李文卿; born December 25, 1948) is a Taiwanese-American mathematician, a Distinguished Professor of Mathematics at Pennsylvania State University. She is a number theorist, with research focusing on the theory of automorphic forms and applications of number theory to coding theory and spectral graph theory. In particular, she has applied her research results in automorphic forms and number theory to construct efficient communication networks called Ramanujan graphs and Ramanujan complexes.