Sir Tim Berners-Lee joins an elite group who have received the honour from the Queen for exceptional contributions in arts, sciences and other areas.
The British academic invented the web's address system and layout in Switzerland in 1991, ultimately revolutionising global communication.
Previously, he was named Greatest Briton at a ceremony in 2004.
Information sharing
Sir Tim was given the honour along with the President of the Royal Society, Lord Rees of Ludlow, and the Rt Rev Lord Eames, ex-Anglican Primate of All Ireland and Archbishop of Armagh.
In 1991, Sir Tim came up with a system to organise, link and browse pages on the net.
He created his hypertext program while he was at CERN, the European Particle Physics Laboratory in Geneva The code he crafted made it far easier for scientists to share their research and information across a fledgling computer network.
He is now director of the World Wide Web Consortium (W3C) at the Massachusetts Institute of Technology in Boston, where he is based as an academic.
The Order of Merit is in the Queen's personal gift, meaning that ministerial advice is not needed.
It is restricted to 24 living members, who are entitled to use the initials OM after their name.
Past recipients have included Florence Nightingale, Sir Winston Churchill, Bertrand Russell, Graham Greene, Sir Edward Elgar, Mother Teresa and Baroness Thatcher.