John Ham

Jo(h)n Ham(m) may refer to:
 * John Ham, MP for New Shoreham in 1433
 * John Ham, co-founder of Ustream
 * John E. Hamm (1776–1864), American colonel, doctor and politician
 * John Hamm (born 1938), Canadian physician and politician
 * Jon Hamm (born 1971), American actor, director and producer
 * Jonathan Hamm (born 1985), former amateur boxer, actor, football player and current mixed martial artist