I assume you're asking after the ethnicity of the actor playing him in The Last Airbender (movie). He was originally cast as Jesse McCartney, but they later recast the role to Dev Patel (who recently starred in Slumdog Millionare). So no, he's not white.

Actually, since they seem to have decided to match the ethnicity of each entire nation to the representative major character, this means that the entire Fire Nation (largely portrayed as villainous) will be cast as people as color, while the heroic Water Tribe is whitewashed.