Jenny McDonagh took £62,000 meant for survivors and spent the funds on trips to Dubai and Los Angeles, expensive dinners and online gambling.
Judge Robin Johnson described McDonagh’s crime as “utterly repugnant”.
“The effect on those who died, their families and friends, cannot be imagined by those who were not directly affected,” the judge said.
“The fact that you, a person who had been given the task of assisting in the aftermath, sought to enrich yourself, is the more shocking in the light of the outpouring of grief and sympathy that followed the disaster,” he added.
The 39-year-old mouthed “I’m sorry, I love you” to the public gallery as she was led sobbing to the cells, the London Evening Standard reported.
McDonagh was first arrested on August 1 and used a stolen card again two days later. Pictures released by the Metropolitan Police showed McDonagh in a central London lobster restaurant, and in new clothes bought with the stolen cash.
Other items paid for by Grenfell funds included £534 on various visits to a hair and beauty salon in Sidcup, and on flights to Paris, Reykjavk, Los Angeles and Dubai – including one she listed as a two week respite break for a genuine victim.
She spent £199.69 on a booking for two at the exclusive Delaunay restaurant in Covent Garden and splurged £113.63 during a visit to the Hippodrome casino in Leicester Square.
McDonagh, from Abbey Wood, south-east London, pleaded guilty to two offences of fraud, one of theft and another of concealing criminal property, at Westminster Magistrates Court last month.
Seventy-two people died as a result of the fire at Grenfell Tower, west London, on June 14 last year. An inquiry into the causes of the blaze, and the emergency response, is ongoing.