In Bangkok the traffic problem has been becoming more and more critical accordingly. In 1971 with the assist from German Government to Thai Government, a group of expert was sent to Thailand in order to study, survey and set a master plan for traffic and transportation in Bangkok, accordingly, a Mass Rapid Transit System was recommended.

     In term of the solution for the travelling and traffic problems in Bangkok, Announcement of the National Executive Council No. 290 dated 27 November 1972 was released to establish the Expressway Authority of Thailand due to construct “Expressway” consisting of express ways and mass rapid transit System that are already proceeded by the Expressway and Rapid Transit Authority of Thailand.

     Later on the government has considered that the road traffic in Bangkok was very stuck so that the operation of MRT should be speed up to ease the people in travelling without private cars. Thus, with the Resolution on 28 July 1992 the cabinet approved to establish a state enterprise under the supervision of the Office of Prime Minister to be responsible for the conduct of the Mass Rapid Transit Project in Bangkok and its vicinities. Consequently, the Royal Decree Establishing the Metropolitan Rapid Transit Authority B.E. 2535 (1992) was announced (published in the Government Gazette, Vol. 109 Part 90 on 20 August 1992) in accordance with the Act on Establishment of the Government Organizations B.E. 2496 (1953).

     Cause of the Royal Decree Establishing the Metropolitan Rapid Transit Authority B.E. 2535 is provided with inadequate provisions for the establishment, management and services of mass transportation with mass rapid transit including to ensure public safety, the Metropolitan Rapid Transit Authority has got the certain limitation to implement its legal authorities and resulting in the inflexibility and inefficiency on services.

     Meanwhile the needs of mass rapid transit has been immensely increasing. Therefore, the Royal Decree Establishing the Mass Rapid Transit Authority of Thailand B.E. 2543 (2000) was announced (published in the Government Gazette, Vol. 117, Part 114 A. on 1 December 2000) establishing Mass Rapid Transit Authority of Thailand, with abbreviation “MRTA” in task of improving the authority and the duties of the Metropolitan Rapid Transit Authority to be able to operate the transit business more systematic and efficient.

     In particularly, the authority to ensure the safety of the operation of train and its passengers. The new state enterprise should be under the supervision of the Office of Prime Minister and has its purposes as the following :Operate the mass rapid transit in Bangkok and its vicinity including in other provinces or between provinces in accordance with the Royal Decree.

1.Operate the mass rapid transit in Bangkok and its vicinity including in other provinces or between provinces in accordance with the Royal Decree.

2.Study, analysis and formulate the project and its plan in concerning to the mass rapid transit regarding to improve and modernize.

3.Perform the business involving mass rapid transit and other business on behalf of the benefit of MRTA and the people using its services.

     In 2002 after the reform in Government agencies, the authority of the Prime Minister in supervision of the Mass Rapid Transit Authority of Thailand was transferred to the Minister of Transport.