Paul Kei Matsuda (born 1970) is a Japanese-born American applied linguist.
He is currently a professor of English and the director of second language writing at Arizona State University He has published several articles and edited books on the areas of second language writing, composition studies, and cognitive and linguistic theories of composition.
He is considered as one of the main theoreticians of second language writing research along with Alister Cumming and Rosa Manchón.