While many models are photoshopped to look picture perfect, the woman in ASOS pictures was not airbrushed for the snap.
Thorpe, who runs a popular plus size fashion blog, shared the snap on Thursday.
She wrote: "Look at this gorgeous model and her cute back rolls just out here to show women that their bodies are normal and that real life isn't photoshopped and filtered."
Her post has now been liked and reweeted over 1,700 times on Twitter, with dozens of other users praising the move.
One tweeted: "This is absolutely amazing. Thank you so much for doing and also showing this. In my opinion, the ''beauty ideal'' is not real. It would be so dull and boring if we all conformed and society and therefore looked/dressed the same as each other."
ASOS was previously praised for its photos of a black plus size model wearing a bright yellow bikini.
Many hailed the choice of model as a "positive step" for the brand - with one person commenting "real bellies matter".
Some suggested that other retailers should follow ASOS's lead by using a more diverse range of models.
Others said it was important for them to see themselves represented by retailers.