The much-travelled Portugal winger, 32, has signed a two-year contract with Espanyol and joins fellow newcomers Joan Capdevila, Sergio Tejera, Diego Colotto and Wakaso Mubarak at the Estadi Cornella-El Prat.
Simao, who counts Barcelona, Atletico Madrid, Sporting Lisbon, Benfica and Besiktas among his former clubs, said: "I'm very happy to wear this shirt, they have an ambitious project here.
"Before signing I spoke with (Espanyol coach Mauricio) Pochettino and he told me what he expected from me and I told him what I can offer the team. The two of us were very clear about everything and now's the time to start work.
"Once I start training with my team-mates, I will know if I can play some minutes this Saturday against Real Zaragoza.
"I've come here to help and all together we can have a great season."