The 23-year-old U.S. citizen was diving in Magdalena Bay off the coast of Baja California Sur state in northwest Mexico on Monday when a shark chomped down on his right forearm, according to a press release from the Mexican Navy.
The man, whose name hasn't been released, apparently managed to swim back to his dive boat and call for help. He was medically evacuated by a naval search and rescue team to the port of San Carlos, where an ambulance transported him to a local hospital for treatment.
The man's wounds are not considered life-threatening, according to the Mexican Navy.
It’s unknown what species of shark attacked him.
A spokesperson for the U.S. Department of State did not immediately respond to ABC News' request for comment Tuesday morning.
ABC News' Joshua Hoyos contributed to this report.