It was in March 2010 that Bessacarr-based Louis underwent his first audition on the ITV show - and to mark the milestone, he shared the flashback picture on Instagram on Monday, showing how he has changed in the last eight years.
The One Direction star, 26, later took to Twitter with a heartfelt tribute to his late mother Johannah Deakin, who was credited for encouraging the singer to share his talent.
Louis chuckled over his appearance as a teen, captioning the image: '8 years ago today. The skinny tie and shirt combo was a must back then.'
The father-of-one rose to fame during his talent show stint, which saw him join boyband One Direction with Zayn Malik, Niall Horan, Harry Styles and Liam Payne.
The group announced their decision to go on an indefinite hiatus in July 2015, a few months after Zayn decided to leave the band.
Louis took to Twitter later that day to share a gushing tribute about his mother, who tragically passed away in December 2016 to leukemia: '8 years today I went for my first audition on the X factor. Thanks you to my beautiful mum for talking me into going! Thank you to each and every person who’s ever supported.'