Tony McArdle has been chief executive of the county council for more than 12 years.
He will hand over his formal responsibilities at the end of February’s full council meeting, although he will continue to work on some key projects until departing for good in the summer after a new chief executive has been appointed.
Mr McArdle has won rich praise for the leadership qualities he has shown during his tenure at the council, whom he joined in September 2005.
The tributes were orchestrated by Coun Martin Hill, leader of the council, who said: “Tony joined the council in difficult times, and has been a key part of its transformation.
“This has resulted in Lincolnshire becoming a high-performing, innovative council, recognised at national level.
“I know I speak for many people when I say we have enjoyed working with him, and wish him every success for the future.”
Mr McArdle said: “It has been a terrific experience for me throughout the time I have been here at Lincolnshire County Council. But the time is right for a change, and I want to make that change this year.
“Lincolnshire is a great authority, and I am proud of all that has been achieved, working with officers and councillors. I will be leaving the council in good shape to meet its ambitions for the future.”
Before coming to Lincolnshire, Mr McArdle was chief executive of Wellingborough Borough Council in Northamptonshire for seven years. He was also an officer in the Territorial Army for more than 20 years.