Alan Glyndwr Cadman, OAM (born 26 July 1937), Australian politician, was a Liberal member of the Australian House of Representatives from 18 May 1974 to 17 October 2007, representing the Division of Mitchell, New South Wales.
Cadman was Parliamentary Secretary to the Prime Minister (Malcolm Fraser) 1981-83 and Parliamentary Secretary to the Minister for Workplace Relations and Small Business 1997-98. In 1992 he was one of a group of Coalition members of parliament who founded the Lyons Forum, a conservative ginger group.
On 16 June 2007, Cadman withdrew from the preselection contest, and later announced his current term would be his last. He was to later condemn the circumstances under which he lost preselection to Alex Hawke. The Australian newspaper wrote "One of parliament's longest-serving MPs has lashed out at the "extreme" right wing of the Liberal Party, saying it is no longer concerned with values or policies and has become obsessed with power for its own sake. Mitchell MP Alan Cadman has broken his silence on the preselection battle in which he lost the party's endorsement for his safe northern Sydney seat, which he won from Labor in 1974, to the right wing's Alex Hawke, 29. Mr Cadman said his loss to Mr Hawke... was the result of relentless branch-stacking within the electorate."
At the time of his retirement Cadman was the second longest-serving member of the House of Representatives (John Howard was elected on the same day as Cadman but took the swearing-in oath later). Philip Ruddock was the only serving member of the House who had served for a longer period of time.