Laporta, who is running for election to once again become president of the club, strategically placed the poster not far where Barcelona's arch-rivals play.
"Excited to see you again," ran the headline on the huge image, with a picture of his face.
Laporta announced at the end of last month that he would be a candidate for the Barcelona presidency after the resignation of Josep Maria Bartomeu in October.
He was formerly president of the club from 2003 to 2010, a period which saw the Catalans dominate on the pitch.
The club won the Champions League in 2006 and 2009 under his watch, in addition to winning La Liga in 2005, 2006, 2009 and 2010.
Laporta was also responsible for hiring Pep Guardiola as coach in the summer of 2008, which concluded in an historic treble in his first season in charge.
The new president of the club is due to be named at the beginning of next year, with elections being held in January.