In his most outspoken intervention on the issue of GM food, the heir to the British throne said that multi-national companies were conducting an experiment with nature that had gone "seriously wrong".
In an exclusive interview with the Daily Telegraph, Charles also expressed the fear that food would run out because of the damage being wreaked on the earth's soil by scientists' research.
He accused firms of conducting a "gigantic experiment I think with nature and the whole of humanity which has gone seriously wrong".
"Why else are we facing all these challenges, climate change and everything?" he asked.
As far relying on "gigantic corporations" for food, he said: "That would be the absolute destruction of everything... and the classic way of ensuring there is no food in the future."
"What we should be talking about is food security not food production - that is what matters and that is what people will not understand. And if they think its somehow going to work because they are going to have one form of clever genetic engineering after another, then again count me out," he said.
"If they think this is the way to go....we will end up with millions of small farmers all over the world being driven off their land into unsustainable, unmanageable, degraded and dysfunctional conurbations of unmentionable awfulness," he added.
The Prince of Wales's forthright comments will put him on a collision course with the international scientific community and Downing Street - which has allowed 54 GM crop trials in Britain since 2000.
His intervention comes at a critical time. There is intense pressure for more GM products, not fewer, because of soaring food costs and widespread shortages.
Many scientists believe GM research is the only way to guarantee food for the world's growing population as the planet is affected by climate change.
They will be dismayed by such a high profile and controversial contribution from the Prince of Wales at such a sensitive time.