A San Francisco native, Robert Hass spent his childhood and youth in the Marin County area of San Rafael. He attended a private Catholic school. He received important encouragement to write from his older brother, who supported his decision to become a full-time writer; and his mother, who was supportive but struggled with alcoholism. Her suffering and its effects on her family are subjects in Hass's most recent poetry collection, entitled Sun Under Wood.

Growing up on the West Coast informed Hass's writing in other ways, and his work is known for West Coast themes and lifestyle. Of course, growing up in the San Francisco Bay area allowed Hass to have a number of opportunities to learn from and observe poets and other artists at work. He was particularly impressed with and influenced by the Beat poets, and began to include East Asian literary traditions in his work, such as Haiku.

The geographical beauty of the Bay area also informed his work, translating the lush, sensuality of the Bay area into poetry. Additionally, coming of age in the 1960s, and living on the West Coast, Hass's politics contributed to the shaping of his work. His first, early marriage to Earlene Leif took place before he completed his undergraduate degree at St. Mary's College in Moraga, California. The couple had three children, all born while he was working on his graduate degrees.

He completed his graduate work at Stanford University in Palo Alto, California, having earned the Ph.D. in English. He began his teaching career at the State University of New York at Buffalo, then later taught at his undergraduate alma mater, St. Mary's College of California, until 1989, when he accepted a teaching position at the University of California, Berkeley.

Hass is the recipient of numerous writing and poetry awards, including the National Book Critics Circle Award in criticism and the National Book Critics Circle Award in poetry. While Hass continues to write and publish, he also translates, and has become a spokesman for literacy, poetry, and ecological awareness. He was appointed Poet Laureate of the United States by the Library of Congress in 1995, and served till 1997 in that capacity.

During his tenure he traveled around the country, lecturing and working in what he calls "places where poets don't go," including boardrooms and civic groups. He also served as Chancellor of The Academy of American Poets from 2001-2007. He is married to poet Brenda Hillman and continues to teach at the University of California at Berkeley.