Filey-based GP Dr Phil Garnett was still working "just a few days before his death" according to the Scarborough and Ryedale Clinical Commissioning Group (CCG), of which he was chairman.
Tributes have been paid to Dr Garnett by colleagues who described him as "erudite, captivating and charming".
Friend and colleague Dr Peter Billingsley, Associate Chair of the CCG, said: "This is an incredibly sad time for the NHS in Scarborough and Ryedale and on behalf of our Governing Body and staff, I would like to express my deep condolences to Phil's family, friends and colleagues at Filey Surgery.
"Phil was driven by a burning desire to make the NHS the best it could be and throughout his time at the helm of our organisation - and indeed throughout his distinguished career as a GP - he was determined to secure the best possible services for patients."
Dr Garnett had nearly 50 years' experience after qualifying in Leeds in 1973 and joining Filey Surgery five years later.
He held senior positions with the local Primary Care Trust, Primary Care Group and St Catherine's Hospice, as well as having a heavy involvement in the North Yorkshire Local Medical Committee.
Dr Billingsley added: "He very much led from the front and was an exceptionally gifted speaker, possessing a wonderful sense of dry humour and wit to match his intellect.
"Phil was erudite, captivating and charming and people always listened to what he had to say."
Following five years' work in secondary care with paediatrics, Dr Garnett gained a Diploma in Child Health from the Royal College of Obstretricians and Gynaecologists and became a Member of the Royal College of Physicians.
Carolyn Liddle, the Practice Manager at Filey Surgery where Dr Garnett's work spanned over 40 years, said: "It is with heavy hearts that we say goodbye to our friend and colleague Dr Phil Garnett.
"He was a GP here in Filey for 40 years and was a much respected and loved doctor.
"The people of Filey will miss him as many of them will have been patients of Dr Garnett for many years. Amongst the sorrow there are smiles from his colleagues at the surgery as we remember a lot of good times."