Frank Keeling, currently senior vice-president and board director at AOL Europe, will replace Mark Danby in the role.
Mr Keeling has been with AOL for four years and played a key role in bringing the Internet group to the UK. He was responsible for launching Netscape Online in August, AOL Europe's first free Internet service provider.
John Pluthero, chief executive of Freeserve, said that Mr Keeling would bring a "wealth of operational experience in the internet market" to the company.
Mr Danby will retain a non-executive directorship at Freeserve but will soon take up a post in a new internet investment company. Freeserve said it planned to invest in the new venture but gave no more details.
Freeserve, which is 80 per cent held by the retailer Dixons, fell 25.5p to 551p.
Freeserve is younger than AOL but has grabbed a larger market share in Europe.