Margaret Ashcroft, senior partner at Landscape Surgery, Garstang, started at the Kepple Lane practice in 1983.
The 60-year-old, who lives in the market town, started as a GP’s trainee and worked her way all the way up.
But she says now is the right time to hang up her stethoscope.
She said: “I have been fortunate to work in the place where I was born and have lived all my life.
“I have really enjoyed my working life at Landscape and have worked with excellent staff and looked after lovely patients.
“I have watched families grow up and am now looking after their children.
“I have now turned 60, over the years I have seen a lot of changes in the NHS and obviously these are still happening and I now feel it is time for me to retire.
“I am looking forward to spending more time with my husband Dave, children Daniel, Megan and Gill and three grandchildren, Hettie, Penelope and Annie.
“We are hoping to do some travelling and I would like to get fitter so I have bought myself an electric bike!
“Finally I would like to say a big thankyou to all the people I have worked with in the past, you have all been great.”
A spokesman from Landscape Surgery said: “It is with great sadness that Landscape Surgery announce the retirement of its senior partner, Margaret.
“She will be greatly missed by the doctors and staff who wish to thank her for the many years of dedication, caring and commitment to looking after the health and welfare of patients in Garstang and the surrounding area and wish her well in her retirement.”