William Cornish

William Cornish may refer to:
 * William Cornish (legal scholar) (1937–2022), Australian legal scholar and academic
 * William Robert Cornish (1828–1896), British physician
 * William R. Cornish (1890–1969), member of the Legislative Assembly of Alberta
 * William Cornysh, also spelt Cornish (1465–1523), English composer and dramatist
 * Willie Cornish (1875–1942), American jazz musician
 * William Crocker Cornish, co-founder of Cornish and Bruce, a railway contracting company in Victoria, Australia