The president of the National Assembly (Thai: ประธานรัฐสภา, RTGS: Prathan Ratthasapha, pronounced [prā.tʰāːn rát.tʰā.sā.pʰāː]) is the presiding officer (speaker) of the National Assembly of Thailand. Since 1992, the office has been an ex officio position occupied by the Speaker of the House of Representatives of Thailand. The president is therefore an MP, usually from the majority party in the House of Representatives. The president is elected at the beginning of a House session immediately after an election, there are no term limits for the office. In the aftermath of the coup d'état in 2014, the function of legislative assembly was turned over to the junta-controlled National Legislative Assembly, which Pornpetch Wichitcholchai, President of the National Legislative Assembly, occupied the ex officio position of President of the National Assembly until the election of Wan Muhamad Noor Matha as Speaker of the House in 2023.
The office of the president of the National Assembly was first established in 1932, with the establishment of the first legislature of Thailand. The office of the president of the People's Assembly of Siam was first occupied by Chaophraya Thammasakmontri (Sanan Thephasadin na Ayutthaya).
The president of the National Assembly, apart from being the presiding officer of the National Assembly whenever there is a joint-sitting, is also the chief representative and leader of the legislative branch in Thailand. In the 2007 constitution the president of the National Assembly is given many powers. The President is assisted by the Vice President of the National Assembly, another ex officio position occupied by the president of the Senate.
The speaker of the House of Representatives is the chief presiding officer of the House of Representatives. The speaker is also entrusted with some legislative powers, as it is his main role to ensure all the legislative process is followed. The speaker is assisted by two Deputy Speakers. The Speaker must act impartially on all matters and therefore cannot be a member of an executive committee of a political party, this also apply to his deputies.
Note: According to the 2007 Constitution of Thailand the office of President of the National Assembly of Thailand is held as an ex officio position by the speaker of the House of Representatives. However throughout Thailand's long constitutional history this has not always been the case, at certain times the office of 'President' of the legislature was sometimes held by the presiding officer of the upper house or that of a unicameral chamber.