Sir Thomas Glemham (c. 1594 – 1649) was an English soldier, landowner and politician who sat in the House of Commons between 1621 and 1625. He was a commander in the Royalist army during the English Civil War.
Glenham was the son of Sir Henry Glemham of Glemham Hall, Little Glemham in Suffolk. After studying at Trinity College, Oxford, he "betook himself to the German wars," serving in armies in Europe from 1610 to 1617. He was knighted on 10 September 1617. In 1621 he was elected MP for Reigate. He was elected MP for Aldeburgh in 1625 and 1626. He then took part as a Captain in the Duke of Buckingham's expedition to La Rochelle. He was captured by the French, but later released. He then served as JP and was involved in several lawsuits and scandals.
In 1639, on the outbreak of the Second Bishops' War Glemham was commissioned a lieutenant-colonel. After the English defeat at the Battle of Newburn, he was Governor of Hull for several months, before returning to London in 1641.
In early 1642, Glemham was part of King Charles's entourage in York. He re-entered Hull unannounced at the head of a large and prestigious party whose purpose was to recover the arms stored there after the Bishops' Wars. The pro-Parliamentarian Governor, Sir John Hotham, thwarted them by inviting them to a lengthy and pointless reception. The impatient King demanded entry to the city and was refused. He proclaimed Hotham a traitor, and Glemham's party was forced to leave.