It is responsible for the operation of rapid transit systems in the Bangkok Metropolitan Region and including other provinces as defined by the royal decree.

Other systems, including the Airport Rail Link, are owned and operated by other agencies.

2535, with the objective of organizing mass transportation systems in Bangkok and its vicinity by electric train.

Under the act, the MRTA has the authority to designate "safe zones" to protect subway tunnels and underground structures and oversee the metro system as a whole.

In addition, the MRTA is able to find income other than passenger fares and can develop real estate as necessary for the benefit of the electric train service and has the authority to operate the electric train business.