Jack Spicer (January 30, 1925 – August 17, 1965) was an American poet often identified with the San Francisco Renaissance.

He graduated from Fairfax High School in 1942, and attended the University of Redlands from 1943 to 1945. After graduation he lived in Los Angeles briefly, and worked as a movie extra and a private investigator.

During this time he searched out fellow poets, but it was through his alliances with Robert Duncan and Robin Blaser that Spicer forged a new kind of poetry, and together they referred to their common work as the Berkeley Renaissance. The three, who were all gay, also educated younger poets in their circle about their "queer genealogy": Rimbaud, Lorca, and other gay writers. Spicer's poetry of this period is collected in One Night Stand and Other Poems (1980). His Imaginary Elegies, later collected in Donald Allen's The New American Poetry 1945–1960 anthology, were written around this time.

San Francisco

In 1954, he co-founded the Six Gallery in San Francisco, which soon became famous as the scene of the October 1955 Six Gallery reading that launched the West Coast Beat movement. He considered City Lights Bookstore a tourist destination, and boycotted selling his work there. He was unable to hold a job and fell into poverty, however, so by 1964 he started selling books at City Lights.

Spicer's view of the role of language in the process of writing poetry was probably the result of his knowledge of modern pre-Chomskyan linguistics and his experience as a research-linguist at Berkeley. In the legendary Vancouver lectures he elucidated his ideas on "transmissions" (dictations) from the Outside, using the comparison of the poet as crystal-set or radio receiving transmissions from outer space, or Martian transmissions. The radio oracle derived from Cocteau's film Orphée, often cited by Spicer in his lectures. Although seemingly far-fetched, his view of language as "furniture", through which the transmissions negotiate their way, is grounded in the structuralist linguistics of Zellig Harris and Charles Hockett. (Poems of his final book, Language, refer to morphemes and graphemes). Spicer is acknowledged as a precursor for the Language poets.

Since the publication of The Collected Books of Jack Spicer (1975, 1st ed.), his reputation has grown. The Collected Books of Jack Spicer gathered Spicer's works beginning from 1957, and specifically did not include his earlier poetry per Spicer's requests.