The former Dallas star was signing posters for devotees outside Pantages Theater in Hollywood on Tuesday night (19Jun12) when one over-eager fan was pulled away by a security official.
In footage obtained by TMZ.com, the bodyguard can be seen throwing punches before bundling the unknown man - who was wearing a leg-brace - to the ground.
As the fan screamed for mercy and told the security worker he was suffering from a leg injury, a clearly shaken Presley urges the bodyguards not to hurt him.
Glancing anxiously at the man as he's pinned to the ground, she tells another guard, "Make sure he's okay. Don't rough him up. I don't like that. I don't want them roughing him up."