The former Strictly Come Dancing star looked unrecognisable, rocking wild curly hair and a see-through, corset-style dress to the 1997 ceremony.
Cringing over her appearance – Louise would have been around 22 at the time – the singer captioned the snaps: "Throwing it back to the Brit Awards...
WATCH: Louise Redknapp's five fashion commandments
"Please can you all remind me to NEVER wear my hair like this again to the Brits!" she added followed by a see-no-evil monkey emoji.
Louise stood next to a youthful Gary Barlow in the pics, but her tight curls were all many of her followers commented on – with some even comparing her to Dirty Dancing star Jennifer Grey – who played Frances 'Baby' Houseman in the cult movie.
"So much like Baby from Dirty Dancing!!" exclaimed one. "Nobody puts Baby in the corner," joked several others, referring to the famous line uttered by Patrick Swayze's character Johnny Castle. A third said: "You look like Jennifer Grey in Dirty Dancing."
Louise looks so different with her curly hair
Others reassured Louise that she shouldn't be embarrassed by her former curly 'do, with one gushing: "You know this is my favourite pic of you ever, gorgeous!" Another wrote: "OMG this is beautiful!"
Fans of the singer are used to seeing Louise sporting long, straight hair – but back in September, she updated her signature style by adding a fringe.
Fans are used to seeing Louise with long, straight hair
The doting mum posted a GIF of herself looking sensational as she showed off her new do, captioning the clip: "Anyone for open bangs? Fringe time."
Louise will also post snaps of her killer outfits, but earlier this month, she revealed she is a huge fan of loungewear and shared tips on how she styles her favourite sweats on her lifestyle blog, Lou Loves.
She wrote: "By teaming a sweat up with a heel and a smart coat or a blazer you can easily create the perfect day to night outfits all year round."
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