Bukele had been expected to secure second term amid soaring approval ratings and virtually no competition.
Bukele on Sunday claimed to have won more than 85 percent of the vote despite electoral authorities not releasing the official results of the poll.
“According to our numbers, we have won the presidential election with more than 85 percent of the votes and a minimum of 58 of 60 deputies in the Assembly,” Bukele said on X before official results were announced, describing the outcome as a “record in the entire democratic history of the world”.
Mexican Foreign Minister Alicia Barcena congratulated Bukele, although the official results had not been announced.
China’s Embassy in the capital San Salvador also congratulated Bukele and his party for the “historic victory”.
With soaring approval ratings and virtually no competition, gang-busting Bukele had been widely expected to comfortably secure a second term.
For the first time since civil war ended in 1992, the Central American country held the election under a state of emergency imposed for Bukele’s crackdown on criminal gangs, which slashed homicide rates but drew criticism for human rights violations.