The Doncaster born star, 30, said that Up All Night — released in 2011 — failed to measure up to the four other studio records that followed.
Louis was the oldest member of the group put together by the judges on TV’s The X Factor on 2010.
The others were Harry Styles, Niall Horan and Liam Payne, all 28, and Zayn Malik, 29.
Louis told an Aussie podcast last week: “Twelve years ago today the band got formed, but the first album was s*** any way.”
He also admitted he feels pressure, as a solo artist, to follow up the success of 1D, who became worldwide stars.
Louis, who is working on his second solo album, said: “There’s still pressure obviously for me to deliver a good record . . . and me trying to find my feet coming out of a band as big as One Direction.”
Zayn quit the group in March 2015, with the remaining four giving their final performance that December.
Speaking in 2016, Zayn labelled the band’s music “generic as f***”. He added: “It wasn’t for me.”
Since the band’s break-up, Louis has launched a successful solo career which included a sell out show at Doncaster Dome.