Mr Pickles agreed with the planning inspector’s recommendation to refuse the appeal.
She had said the turbines, which would overlook Stewkley, Soulbury and Drayton Parslow ‘would be harmful to the character and appearance of the landscape’.
The developer now has six weeks to challenge the decision via the High Court.
Malcolm Newing, chairman of the Stop Dorcas Lane Wind Turbine Action Group, said: “This is truly fantastic news and the best Christmas present that we could have asked for.
“The Secretary of State’s decision is a hugely important one and we remain absolutely convinced that common sense will finally prevail and this ill-judged development – driven by financial greed rather than any well-intended or well-planned green agenda – is about to be laid to rest for good”.
The action group has been fighting the proposed wind farm since it was first announced back in July 2011.
Mr Newing added: “Our success in taking on and defeating the developer Force 9 Energy and their financial backer EDF is, in its entirety, due to the hard work of a few and the great support – financial and emotional – of many.
“We are indebted to our district councillors Neil and Janet Blake and our local MP John Bercow for their help and advice and all six local parish councils for their unwavering support.
“Most of all we are grateful to all the local residents for always rising to the challenge, whether it be attending events, providing donations or signing petitions and writing letters. It has sustained us when we have been at our lowest ebb to know the level of support on which we could count.”