At his first speech as leader to the NHS Confederation conference, Mr Cameron said he wanted to see 'evolution not revolution'.
He said: 'When Labour came to power in 1997 the first thing they did was scrap the reforms of the last ten years.
'Now, ten years on they are slowly and painfully trying to get back closer to the system they inherited.'
Mr Cameron set out 'four progressive stages' he wanted to see take place: committing increasing resources to the NHS; devolving power and responsibility to the front line; 'setting the NHS free from political interference in day to day management'; and the 'transformation of the Department of Health into the Department of Public Health'.
He said the Conservative's creation of an 'internal market' in the 1990s was not perfect but was now 'universally accepted'.
Mr Cameron added: 'We have a duty not to subject the NHS to further unnecessary reorganisation.'
The Conservatives would 'set in stone' the 10 core principles of the NHS in law.
He went on: 'I pledge that a Conservative government will increase spending on the NHS year on year.'
Any reduction in acute care would be 'matched by the spending on social care and long-term healthcare that longer lives and good health demands' he said.
Mr Cameron said central Department of Health control 'has turned into a nightmare of central-driven priorities, targets and inspections under the Blair-Brown administration'.
Mr Cameron cited the survey in this week's HSJ of managers and clinicians, which he said shows 'morale is now rock-bottom throughout the NHS'.
He promised a new national watchdog to 'monitor NHS services and act as a champion for patients'.
And Mr Cameron added: 'We will scrap politically-driven targets that prescribe processes rather than measure outcomes.'
Accountability would be better served by an independent board for the NHS, he said 'composed of professional clinicians, managers and senior executives'.
He added: 'Ministers, accountable to parliament, will be responsible for the overall framework of the NHS.'
Once the NHS has 'the money it needs - patients and professionals are properly in charge - and when the independence of the NHS is guaranteed', then the role of the DoH should change to focus more on public health.
Mr Cameron said: 'In the field of healthcare, I want the health secretary to concentrate on public health above all.'
The current problem was 'lack of effort and follow-through' and the party would transform the 'Cinderella' public health system.
After the speech, Plymouth primary care trust chief executive John Richards said: 'I think there is little to disagree with. The devil will be in the detail.'
'We welcome to commitment to building on things they recognise as having worked and the emphasis on public health.'
But one mental health trust non-executive director, who did not want to be named, said: 'It was current policy under a different spin, it did not have a great level of detail which you would expect.
'A lot of what was said is already happening and if there was anything different it would have stood out.'
PA Consulting Group partner Howard Lyons: 'I thought it was very encouraging. It seemed reasonably well thought through and they do seem to be putting a lot of effort into thinking through the future of the health service - what things don't work, what things are working that they are going to retain.'
'They have looked at this in depth. The fact that Stephen Dorrell has been behind it will be a great encouragement to many.'