James Jason Poyser (born January 30, 1967) is an American songwriter, record producer, musician and current member of the hip hop band The Roots.

Poyser officially joined The Roots in 2009, composing and performing live as the house band for NBC's Late Night with Jimmy Fallon, and subsequently The Tonight Show Starring Jimmy Fallon. He is sometimes used as comic foil, especially for his use of deadpan facial expressions, and is frequently used as the pianist for Fallon's "thank-you notes" after the monologue ends.

His work in film and television include composing theme songs for shows such as Wyatt Cenac's Problem Areas, Hawthorne, The Break with Michelle Wolf, contributing music to the TV shows The Equalizer, Black-is, The Chappelle Show, and to the movies Fame, Dave Chappelle's Block Party, and Totally Awesome, among many others.