Rajane Ga Silva bought a Woolworths chicken in Revesby, NSW, on Saturday, as she does on most Saturdays.
'We often buy the Woolworths BBQ - basically once a week,' she told 7 News.
'It makes things easier if we're busy with work - we've never had a problem but I don't know if I'll buy it again now.'
Ms Ga Silva said she was tearing the chicken up when her son took a piece and ate it.
It was then that she noticed things crawling around inside of it and described them as 'worms.'
'I don't know if he is going to get sick now,' she said. 'I have to take him to hospital or the doctors now and see if he will have a reaction.'
Ms Ga Silva took the chicken back to the store to get a refund.
'I saw some things moving inside and I was just disgusted, I don't know how else to describe it,' she said.
Woolworths is yet to make a comment.