Michael Armand Hammer (September 8, 1955 – November 20, 2022) was an American businessman. He was the son of Julian Armand Hammer and the grandson of industrialist Armand Hammer. Best known for his ties to Occidental Petroleum, the company of his late grandfather, Hammer oversaw the Hammer International Foundation, the Armand Hammer Foundation, and owned numerous businesses that included Hammer Galleries, and Hammer Productions, a television and film production company located in Los Angeles, California.

Hammer sat on the board of directors and the executive committee for the Los Angeles Dream Center, and was on the Investment Committee and Board of Reference for Oral Roberts University. Hammer was the owner and chief executive of the Knoedler, an art dealership in New York City, which closed in 2011 after purchasing and reselling $80 million in forged paintings bearing the signature of abstract expressionists such as Mark Rothko and Jackson Pollock.