The meeting is a late addition to Brown's tightly packed schedule, which is dominated by formal meetings with government officials and receptions for business leaders.
In another change to Brown's agenda, the governor is now expected to address the controversy over migrants entering the United States -- a topic that has roiled U.S. politics. Brown is scheduled to appear with the archbishop of Los Angeles and Central American religious and diplomatic officials on Tuesday afternoon.
So far, the governor's comments on the issue have been limited, apart from calling it "a humanitarian problem."
Brown hopes that the visit, which comes one year after a similar trip to China, fosters more trade across California's southern border and closer cooperation with Mexico on issues such as climate change.
The governor's meeting with the Mexican President Enrique Peña Nieto, is closed to reporters. Brown has invited him to visit California later this year, although a date has not yet been announced.
Peña took office less than two years ago and has made ambitious promises to improve the country's economy, reform its government and decrease violence fueled by the drug trade.
Progress, however, has been elusive, In particular, economic growth has fallen short of government goals.
"Mexico is growing," Finance Minister Luis Videgaray said in May, but "it is definitely not the growth that Mexico needs."
Still, there are signs the middle class is expanding, said Christopher Wilson, who studies the Mexican economy at the Wilson Center think tank in Washington.
"There are lots of opportunities for the United States to tap into," he said.
That's a hope shared by the governor and the scores of business representatives who joined his trip to Mexico City. On Sunday night, they're scheduled to mingle at a reception in the downtown hotel where members of the California delegation are staying.