The National Assembly of Quebec (French: Assemblée nationale du Québec, pronounced [asɑ̃ble nɑsjɔnal dy kebɛk]) is the legislative body of the province of Quebec in Canada. Legislators are called MNAs (Members of the National Assembly; French: députés). The lieutenant governor of Quebec (representing the King of Canada) and the National Assembly compose the Parliament of Québec, which operates in a fashion similar to those of other Westminster-style parliamentary systems. The assembly has 125 members elected via first past the post from single-member districts.

The National Assembly was formerly the lower house of Quebec's legislature and was then called the Legislative Assembly of Quebec (French: Assemblée législative du Québec). In 1968, the upper house, the Legislative Council, was abolished and the remaining house was renamed. The office of President of the National Assembly is equivalent to speaker in other legislatures. As of the 2022 Quebec general election, the Coalition Avenir Québec (CAQ) has the most seats in the Assembly.

The Constitutional Act 1791 created the Parliament of Lower Canada. It consisted of two chambers, the Legislative Council and the Legislative Assembly. That parliament and both chambers were abolished in 1841 when the Act of Union 1840 merged Upper Canada and Lower Canada into a single province named the Province of Canada. The Act of Union created a new Parliament of the Province of Canada, also composed of a Legislative Council and a Legislative Assembly. That Parliament had jurisdiction over the entire province, with members from Lower Canada and Upper Canada in both houses.

The Constitution Act, 1867 (formerly known as the British North America Act), created the Dominion of Canada, and also created the provinces of Ontario and Quebec by splitting the old Province of Canada into two, based on the old boundaries of Lower Canada and Upper Canada. The act created a new bicameral Legislature for the province of Quebec, composed of the Legislative Council and the Legislative Assembly of Quebec.

In December 1955, the assembly passed a bill according the title "Member of Provincial Parliament" (membre du Parlement provincial) and the initialism "MPP" (M.P.P.) to members of the legislature. Previously, there had been no fixed designation, but they had often been referred to as "Members of the Legislative Assembly" (MLAs) (membres de l'Assemblée législative (M.A.L.s)), which Premier Maurice Duplessis noted in his speech on the bill, "can sometimes be pronounced as 'mal', which means 'evil' in French."

In 1961, Marie-Claire Kirkland became the first woman elected to the Legislative Assembly.

In 1968, Bill 90 was passed by the government of Premier Jean-Jacques Bertrand, abolishing the Legislative Council and renaming the Legislative Assembly the "National Assembly", in line with the more strident nationalism of the Quiet Revolution. Before 1968, there had been various unsuccessful attempts at abolishing the Legislative Council, which was analogous to the Senate of Canada. With the adoption of the new name, members of the assembly were now designated Members of the National Assembly (MNA) in English. In French, they are referred to as either membre de l'Assemblée nationale with the initialism M.A.N. or as députés de l'Assemblée nationale du Québec.

In 1978, television cameras were brought in for the first time to televise parliamentary debates. The colour of the walls was changed to suit the needs of television, and the salon vert (green hall) became the salon bleu (blue hall).