Police say 86-year-old Guy Swan Jr. of Pompton Plains was killed. The accident occurred shortly before 9 a.m. Tuesday in Vernon Township, Sussex County.
The school bus was taking 37 elementary students to Rolling Hills Primary School.
Officials say 21 students were taken to two hospitals as a precaution. Their injuries were minor.
The man who died is the father of Army Lt. Gen. Guy Swan III, commander of U.S. Army North. His responsibilities include homeland defense and military relations with the armies of Canada and Mexico.
The cause of the accident is under investigation.