Mrs Cooper, of Haslingden, has been involved with Scouting for the last 35 years and is currently the District Commissioner for Rossendale as well as being the Centre Manager at Crawshawbooth Community Association.
Since 2014, she has also been a Trustee for the community charity, Kids in Rossendale, raising money for underprivileged children.
In 2020, Mrs Cooper was awarded the British Empire Medal in The Queen's Birthday Honours List for her services to children and young people in Rossendale.
Lord Shuttleworth said: "I am delighted that Mrs Cooper has agreed to join the Lieutenancy and will be available to support me and help with the many organisations and people with which the Lieutenancy works."
Mrs Cooper will join the existing team of Deputies who help and support the Lord-Lieutenant in his duties as Her Majesty The Queen’s representative in the county of Lancashire.
The Office of Lord-Lieutenant is military in origin and dates from the reign of Henry VIII when the holder was responsible for the maintenance of order and for military purposes relating to local defence.
Lord-Lieutenants are Her Majesty’s personal representative in a county or area.
The function of a Deputy Lieutenant is to assist the Lord-Lieutenant in carrying out his public duties.
The role includes arranging visits by members of the Royal family and escorting Royal visitors.