Mason Sundberg, 8, of Sudbury was identified by his family after a tree fell on him around 10:45 a.m. Tuesday at YMCA Camp Chickami in Wayland.
The falling tree also injured a camp counselor, who suffered minor injuries, while Mason was flown to Massachusetts General Hospital in Boston and later died.
Camp Chickami, founded in 1955 for children ages 7 to 15, closed for the rest of the week as grief counseling was arranged for campers, families and staff.
Sudbury Public Schools said Mason was a student at Loring Elementary School and worked with the Northeastern Massachusetts Law Enforcement Council's STARS team to provide crisis support.
Wayland officials called the death a tragic accident as the community mourned and Mason's family said details on remembrances and a celebration of life would be shared later.