Dennis Poirier grew up in Gloucester, Massachusetts. He began his formal studies at Butera School of Art in Boston, then returned to Cape Ann to study with John C. Terelak and Ted Goerschner at the newly formed Gloucester Academy of Fine Arts. Later he moved to New York City to study at the Arts Student League winning the Charles J. Romans Memorial Award at his very first national exhibit at the Allied Artists of America Show.

Dennis is a member of many prestigious art associations including the Oil Painters of America, North Shore Arts Association,Rockport Art Association, the Copley Society of Art (a Copley Artist), the Hudson Valley Arts Association, and the Academic Artists Association.