Miami-Dade police say Alexander Sanghwan — listed as being from Ontario — was walking on the edge of a road around 5:30 a.m. on Sunday when he was struck.
Detectives said in a statement issued on Sunday that Sanghwan was hit by a navy blue, 2010 BMW 335i, and the driver fled the scene without stopping to help.
A police spokesman says no arrests have been made and the traffic homicide unit is investigating.
The spokesman said Monday afternoon that Sanghwan remained in hospital with multiple injuries and was in critical condition.
Miami TV station WSVN quoted Sanghwan's mother as saying he was visiting Florida to attend the 2015 Ultra Music Festival in downtown Miami.
"He does have bleeding on the brain, so they're doing CAT scans just to monitor the situation," Patricia Sanghwan told WSVN. "Right now, it's quite early, so we can only be hopeful that he will take a turn for the better and not the worse."