澳大利亚民主党（Australian Democrats）是澳大利亚的政党。

澳大利亚民主党1977年建党，由原有的两个小党合并，加上部分从日趋保守主义的澳大利亚自由党退党的倾向于古典自由主义的党员。

民主党建党后以“第三势力”、“中间路线”的姿态迅速发展，曾为澳大利亚参议院的第三大党，全盛时期在八十至九十年代，由于先后执政的澳大利亚工党和自由党-国家党联盟一直未能控制参议院，因此在审议部分法案时民主党可左右政府的决策。民主党的衰败始于1999年。当时执政的霍华德政府意欲推行消费税，但霍华德的自由党联盟未控制参议院而不得通过。当时参议院内的其他议员（包括工党、绿党和独立议员）都反对，民主党在之前竞选时也持反对意见，但民主党最终和霍华德达成交易，助其通过消费税，使得当初投票给民主党的选民大失所望。之后民主党的支持率大幅下滑，再加上内部矛盾和领袖危机，在2004年大选中民主党支持率跌至2.4%，联盟党控制参议院。2007年大选中民主党失去所有议席。民主党的第三党地位由澳大利亚绿党所代替。自2012年起，民主党中央党组织分裂成数个组织，互相争夺民主党作为注册政党的领导权。

The Australian Democrats was a centrist political party in Australia with a social-liberal ideology. The party was formed in 1977, a merger of the Australia Party and the New Liberal Movement, with former Liberal minister Don Chipp as its high-profile leader. Though never achieving a seat in the House of Representatives, the party had considerable influence in the Senate for the following thirty years. Its representation in the Parliament of Australia ended on 30 June 2008, after loss of its four remaining Senate seats at the 2007 general election. As of October 2012, the organisation had disintegrated and control was contested by two factions associated with two former parliamentarians. The party was deregistered by the Australian Electoral Commission on 16 April 2015 due to the party's failure to demonstrate requisite 500 members to maintain registration. Even before its deregistration and since it became extinct as a parliamentary party anywhere in Australia, the party saw many of its prominent members including former federal party leader Andrew Bartlett and former NSW MLC Arthur Chesterfield-Evans defect to the Greens.