Jane Clarke joins the council in August after an extensive career in public sector comms, including seven years at the Foreign and Commonwealth Office (FCO).
Kent is the largest shire authority in the country, with a population of 1.4 million and an annual budget of £2.4bn. It has more than 44,000 staff, including those based in schools.
A key focus for its comms team is deterring young people from drug and alcohol abuse, smoking and risky sexual behaviour.
Kent chief executive Peter Gilroy said: 'We work in a challenging environment of finding new ways to reach and communicate with the public, including new media developments such as broadband TV, blogging and social networking.
Jane's background will help Kent move forward in using these innovations and maintaining our already excellent record as a four-star authority.'
For the past two years, Clarke has overseen all internal and external communications at Sport England, a non-departmental public body and Lottery distributor that works to increase participation in sport.
While at Sport England, Clarke relaunched its parliamentary sports fellowship scheme and launched Sport England's active people survey - the largest-ever survey into the sport and recreational habits of the people of England.
During her seven years at the FCO, Clarke covered roles including head of TV and radio, head of strategy and campaigns and, latterly, head of internal comms.
She has worked on promotional campaigns such as Think UK in China in 2003 - Britain's largest-ever overseas promotional campaign funded by Government.
Tanya Oliver is currently managing the comms unit at Kent on an interim basis, in addition to her role as head of the council's strategic development unit.