Pumpkinhead (also known as P.H., born Robert Alan Diaz on Sept. 17th, 1975) is an American rapper and hip hop artist of Latino descent. He grew up in the Park Slope area of Brooklyn, New York with his mother and younger sister.

Pumpkinhead started as a bboy at age 10. He began writing rap lyrics during his 6th grade language arts class after hearing the song "Nightmares" by Dana Dane. He also stated he was influenced by Redman and the Leaders of the New School, as well as Doug E. Fresh. He also cites his experience of meeting 2Pac and witnessing his ability to write and record songs on the spot as a motivating factor in his emceeing.