The 41-year-old, who won the World Cup with Argentina in 1986, had been refused permission to enter Japan because of his history of drug abuse.
But officials relented and allowed Maradona into the country because of his legendary status in football and the fact that the World Cup is only held every four years.
"You are my god," said one fan waving an Argentine flag.
Maradona, who has been undergoing drug rehabilitation treatment in Cuba, is expected to watch the final between Brazil and Germany in Yokahama on Sunday.
Last week Maradona got the most votes in Fifa's internet poll of fans to choose a World Cup dream team.
His second goal against England in their 1986 quarter-final was also voted Fifa goal of the century.