Hendrik S. Houthhakker, professor of Economics, will be the third member of President-elect Nixon's Council of Economic Advisers, it was revealed yesterday.

Paul W. McCracken, Chairman-designate of the Nixon council, announced the appointment, which completed the three-man group.

Houthhakker, a Dutch-born authority on international monertary problems and the balance of payments, joins McCracken and Herbert Stein, a senior fellow at the Brookings Institution in Washington, D.C., on the new council.

Calls for Reform

At a news conference following the announcement yesterday, Houthhakker criticised the present international monetary system and called for reforms to prevent a recurrence of the crises of recent years.

The economist also expressed optimism about the U.S. domestic economy, calling those who predict a recesion this year "extreme."

For the past year, he has been on leave of absense from Harvard to serve as staff member of President Johnson's Council of Economic Advisers.

He has served as a visiting professor at the University of Toyka and M.I.T., and was a staff member of the Cowles Commission for Economic Research at the University of Chicago. He taught at Stanford for six years before coming to Harvard in 1960.

Consumer Demands

Houthhakker is also known for his contributions to statistics and consumer economics. He is the co-author of "The Analysis of Family Budgets" with S.J. Prais. His other works have examined consumer demands in the world markets and the effect of government policy on commodity markets in the U.S.

Nixon is expected to announce soon appointments to several other major posts, including the prestigious Ambassadorship to England. Informed sources have indicated that Walter W. Annenberg, a millionaire publisher, will probably get that appointment, while Kenneth B. Keating, former U.S. Senator from New York and now a state judge, is in line for the Ambassadorship to Israel.