Jigme K. Norbu, 45, was killed Monday night in Palm Coast in northeastern Florida. He had been participating in the first day of a 300-mile "Walk for Tibet," from St. Augustine to West Palm Beach.
"Yes, it is true unfortunately," Tempa Tshering, a representative of the Dalai Lama in New Delhi, told CNN.
Norbu, of Bloomington, Ind., was the son of the Dalai Lama's late older brother.
He had walked in several other marches, including a 900-mile trek from Indiana to New York in 2009, The Associated Press reported.
He was hit by an SUV while walking near the edge of the southbound side of State A1A.
The driver, Keith O'Dell, 31, was questioned by state police and was not charged, Central Florida News 13 reported.
Norbu's father, Taktser Rinpoche, who died in 2008, was a high-ranking lama and abbot of a monastery when the Chinese invaded, the AP said, and the brothers went into exile after the 1959 uprising.