"I think his energies, intelligence and passion could be both of service and servicing to him, as it is to all who are touched by the struggle of the Haitian people," Penn said in a statement Friday.
"Charlie is one of the very few public people who cannot be accused of using the media to his own benefit. I would very much like to show my old friend the world of needs on the ground in Haiti, and introduce him and his tremendous wit to our hard working Haitian staff."
Penn's message of support came hours after Sheen told "Access Hollywood" that he and Penn were planning a trip to the Caribbean nation, although no date for their travel has been announced.
"If he chooses to give support, I'll trust it," the Academy Award winner said.
Sheen, who has been on a media blitz since Monday, says he would like to bring the attention of the world back to Haiti, where Penn has been a fixture since a January 2010 earthquake destroyed more than 500,000 homes.