Venus and Adonis is an opera in three acts and a prologue by the English Baroque composer John Blow, composed no later than 1684 and no earlier than 1681. It was written for the court of King Charles II at either London or Windsor Castle. It is considered by some to be either a semi-opera or a masque, but The New Grove names it as the earliest known English opera.

John Blow was an English composer and organist of the Baroque period. Appointed organist of Westminster Abbey in late 1668, his pupils included William Croft, Jeremiah Clarke and Henry Purcell. In 1685 he was named a private musician to James II. His only stage composition, Venus and Adonis, is thought to have influenced Henry Purcell's later opera Dido and Aeneas. In 1687, he became choirmaster at St Paul's Cathedral, where many of his pieces were performed. In 1699 he was appointed to the newly created post of Composer to the Chapel Royal.