The International Institute for Strategic Studies (IISS) had named the room in his honour.
The honour is the first of its kind. Some other rooms at the institute are also named, but mostly for corporate sponsors.
The Lee Kuan Yew Conference Room stands on a serene corner on the fifth floor of Arundel House, which houses the institute, a leading authority on political-military conflict.
Sponsors of the room include the Singapore Press Holdings Foundation, Keppel Corporation, DBS Bank and the estate of the late banker and hotelier Khoo Teck Puat.
They donated an undisclosed sum for the room as part of the IISS' 50th anniversary fund-raising drive.
IISS director-general and chief executive John Chipman, who described Mr Lee as 'Asia's leading strategic thinker', said a host of strategic thinkers had also spoken at the institute.
They include popular British opposition leader David Cameron, and the late Benazir Bhutto, who was a former prime minister of Pakistan.
The room, with freshly painted walls in a golden ochre, was filled yesterday with close to 200 guests.
Other sponsors who contributed to the room named after MM Lee are Hotel Properties, Reef Holdings, Singapore Technologies Engineering, SembCorp Industries and Hong Kong's Sino Group, a property developer.
LEE SIEW HUA