John Brewer may refer to:
- John Brewer (American football, born 1906) (1906–1980), American football player
- John Brewer (fullback) (1928–1983), American football player
- John Brewer (bishop) (1929–2000), fourth Roman Catholic Bishop of Lancaster, England
- John Brewer (historian), professor of history at Caltech and winner of Wolfson Prize in History
- Johnny Brewer (1937–2011), American football tight end and linebacker
- John Sherren Brewer (1810–1879), English clergyman, historian and scholar
- John David Brewer (born 1951), English sociologist
- J. Hart Brewer (1844–1900), American Representative for New Jersey
- J. Mason Brewer (1896–1975), American folklorist
- John Brewer (MP), British Member of Parliament for New Romney
- John Brewer (monk) (1744–1822), English Benedictine monk
- John Brewer (politician) (1800–1870), American farmer and politician in Michigan
- John Brewer (athlete) (1950-2022), American Paralympic medalist