Former Secretary of State Alexander M. Haig Jr. yesterday was named chairman of United Technologies Corp.'s new advisory committee on "global business policies."

Haig, who resigned as Secretary of State last June, was president of United Technologies from December, 1979 until he joined the Reagan administration in January, 1981. Before that he headed NATO forces in Europe and was chief of the White House staff when former president Nixon resigned in 1974.

United Technolgoies chairman Harry J. Gray said Haig, 57, will be a consultant on a "variety of domestic and international business matters" for United Technologies. Gray said the advisory committee Haig will chair will be made up of "world leaders in industry, finance and government affairs." No other members of that committee have been named yet.

In addition to his part-time duties at United Technologies, Haig also will be a visiting lecturer at Princeton University this fall and has joined the Hudson Institute for policy research. The Hudson Institute, located in a small Hudson River hamlet not far from New York City, was founded by analyst and futurist Herman Kahn 21 years ago.

The institute conducts research for private and government clients in areas ranging from defense to economics to "future studies."