James, Jim, Jimmy or Jimmie Williamson may refer to:
Arts and entertainment J. C. Williamson (James Cassius Williamson, 1845–1913), American-Australian theatrical actor, producer and manager James Williamson (film pioneer) (1855–1933), Scottish film-pioneer James Williamson (musician) (born 1949), American guitarist, songwriter and record producer
Law and politics James Williamson (New South Wales politician) (1811–1881), Australian politician James Williamson (New Zealand politician) (1814–1888), New Zealand politician James Williamson (Victorian politician) (1831–1914), Australian member of the Victorian Legislative Council James Williamson, 1st Baron Ashton (1842–1930), British businessman and Liberal Party politician James Allen Williamson (born 1951), American politician in Oklahoma
Religion James Williamson (priest) (fl. 1723–1736), English Archdeacon of Lewes James Williamson (mathematician) (1725–1795), Scottish minister and mathematician, joint founder of Royal Society of Edinburgh James DeLong Williamson (1849–1935), American minister and president of Western Reserve University
Sports Jimmy Williamson (1928–2015), Scottish footballer James Williamson (Australian cyclist) (1983–2010), Australian journalist and cyclist James Williamson (New Zealand cyclist) (born 1989), New Zealand cyclist
Others James Alexander Williamson (1829–1902), Union general in the American Civil War James Williamson (historian) (1886–1964), English historian of maritime exploration James F. Williamson (fl. from c. 2000), American architect and author Jimmie Williamson, American community college leader