LMCs at the annual conference in Liverpool said the QOF is now so complex, in particular the new quality and productivity (QP) indicators, that it is affecting GPs' capacity to address individual patient needs.
LMC representatives demanded no changes are made for the next two years 'in order to accommodate the changes to commissioning'.
The vote puts pressure on the GPC to toughen its negotiating stance over QOF when it meets with NHS Employers later this year to negotiate the 2013/14 QOF.
Proposing the motion, Dr Paula Cowan of Wirral LMC said the original idea of QOF had been evidence-based targets to improve standards, but that the types of indicators approved had since changed.
'This has seen highly qualified GPs pouring over reams over data, but not true clinical evidence, about referrals and emergency admissions in an attempt to reduce both, which is ultimately trying to reinvent the wheel,' she said.
'Meanwhile, back at the ranch, patients still need to be seen and the sick need to be healed.'
She added: 'Why should this voluntary box-ticking exercise increasingly determine our outcome?
'It would seem now to be less about the "Quality and Outcomes Framework" and more about "Quashing Our Freedom" to deliver care in general practice tailored to the need of our patient population and those who don't fit into the QOF box.'
She said while cost effective delivery of services in times of austerity was prudent, this should not be in a way that 'prevents us from doing what we are good at, what we are trained to do, and at a constant detriment to our patients'.
Chairing the session, GPC member Dr David Bailey said the Commonwealth Fund had suggested the individual care GPs provide to their patients had significantly increased since QOF was introduced.
He said if LMCs voted to back the motion that QOF was interfering with core GP care it would suggest QOF is not working in the best interest of patients, which he 'did not believe was true'.
However, Dr Bailey said the GPC would be 'delighted' to be able to negotiate no changes in QOF apart from clinically necessary ones, although he said it may be 'tricky' to negotiate. 'We'd like a bit of stability,' he added.
The conference also voted to reject the DH's concept of 'an increasingly QOF-based system for calculating practice income.