New Zealand Prime Minister Robert D. Muldoon yesterday told a crowd of 75 at the Kennedy School that a new economic order needs to be established before the international monetary system collapses.

Muldoon said the reforms should be drafted by a high-level summit of economists and world leaders, similar to the Bretton Woods conference of the 1940s which set world trade policies, exchange standards and loan policies for decades to come.

Muldoon, the former chairman of the Joint Board of Governors of the International Monetary Fund and World Bank, called Bretton Woods "the most remarkable economic experiment the world had ever seen or has seen since," but added that a new agreement should be tailored to the problems of the '80s.

The prime minister told the crowd that he hopes a preliminary committee of international experts will be established to investigate such problems as protectionism, the lack of direct foreign investment in the Third World, and the rescheduling of payments on international debts.

The chairman of the Council of Ministers of the Organization for Economic Cooperation and Development, Muldoon is considered to be at the forefront of the international financial scene. For the past week, he has been in Washington soliciting support from the Reagan administration for his cause. But Muldoon added that he expects limited success "Governments, like people, resist change."