The law appeared in the Diario Oficial de la Federacion, an official government publication, and was praised by Lopez Obrador, commonly referred to as AMLO, in a video address online.
"We have a majority in Congress and changes have already begun. There’ll be no more pensions for former presidents. A law has been adopted and published," he said.
AMLO said in the address he would be paid 40 percent of what incumbent Enrique Pena Nieto earned after he assumed office in December. He would not be compensated for expanses.
Monthly payments to each of the Mexican former leaders are estimated at a monthly 205,000 pesos ($10,300), although some of them said they had opted out or spent it on charity.