The 6-8, 240-pound James became the second high school player taken with the No. 1 pick.
James has already received a $90 million endorsement contract and has caused a jump in ticket sales.
The rest of the top 10 was made up of Dwayne Wade of Marquette to Miami; Chris Kaman of Central Michigan to the Los Angeles Clippers; Kirk Hinrich of Kansas to Chicago; T.J. Ford of Texas to Milwaukee; Mike Sweetney of Georgetown to New York and Jarvis Hayes of Georgia to Washington.
Nine college seniors, four high schoolers and eight international players were taken in the first round.