Yellen's family immigrated to the United States when he was five. He attended the University of Michigan and on graduating became a reporter on the Buffalo Courier in Buffalo, New York. He is best remembered for his collaboration with composer Milton Ager. He and Ager entered the music publishing business as part owners of the Ager-Yellen-Bernstein Music Company.
He died in Concord, New York.
- What's in a Name? (1920) with music by Milton Ager
- Rain or Shine (1928) with music by Milton Ager
- Follow A Star (1930) with music by Vivian Ellis
- You Said It (1931)
- George White's Scandals of 1935
- George White's Scandals of 1939
- Boys and Girls Together (1940)
- Alabama Jubilee 1915
- Louisville Lou 1923
- Hard Hearted Hannah (The Vamp Of Savannah) 1924
- I Wonder What's Become of Sally 1924
- Cheatin' on Me 1925
- In Your Green Hat 1925
- My Yiddishe Momme 1925 with music by Lew Pollack. A huge success for Sophie Tucker.
- Crazy Words, Crazy Tune 1926
- Ain't She Sweet 1927
- Happy Days Are Here Again 1930