Lily wasn't just there to see the show, which she described on Twitter as 'lovely', but she also told photographers she was meeting Chanel designer Karl Lagerfeld about designs for her wedding gown.
She said: 'I'm here to see Karl for my wedding dress.'
The 25-year-old is set to wed fiance Sam Cooper later this year.
Lily's appearance at Paris Fashion Week comes as she revealed the pain of her two miscarriages in a clip from her new documentary Lilly Allen: Riches to Rags, a programme that charts the opening of her Covent Garden vintage boutique store, Lucy in Disguise.
The programme, which followed her from March to October last year, also reveals that she has suffered with an eating disorder, as well as following her fashion pursuits and revealing her dreams for the future.
The show starts on Channel 4 on 15 March at 10pm.
See more stars front row at Paris Fashion Week