The University of Navarra's Economics, Sport and Intangibles Research Group calculated "media value" by monitoring internet presence and the volume of press articles and gave Argentina forward Messi the top ranking for players of 21.6 points.
Real's record signing, Portuguese international Cristiano Ronaldo, was second with 19.6 and Manchester United's England striker Wayne Rooney third with 13.6.
European and world champions Barca topped the clubs' ranking with 96.6 points thanks to their haul of six trophies in 2009, with Real jumping to second, on 83.0, from fifth in a similar study published in June 2009.
"There has never before been a similar gain in media value in such a short time in the five seasons we have been conducting this study," author Francesc Pujol said of Real's climb up the club ranking.
Pujol, a professor of economics, said the club's higher media value suggested they would be able to earn more from commercial activities such as marketing and merchandise that would help offset the huge outlay on players and wages.
However, he warned that the initial boost would only be maintained if Real were successful in Europe's top club competition, the Champions League, in coming seasons.
