The former Beach Boys star has been performing at the Royal Festival Hall for a six-night run that ends Saturday, NME.com reported Thursday.
"Performing 'Smile' brings back lots of memories for me and I feel like the audience are all my friends, every night," Wilson said.
"We're really blowing peoples' minds. When we get to the encores, I feel like the roof is lifting off the hall and we're all going to take off," he said.
After singing Beach Boys' hits, Wilson performs "Smile" in full at each show.
The concept album, originally set for a 1967 release, was never finished because Wilson suffered a nervous breakdown. Through the years, the project has gained almost mythical status among fans, NME.com said.