C. Clyde Ferguson Jr., 53, former U.S. ambassador to Uganda and a former dean of the Howard University School of Law, was elected yesterday as president of the American Society of International Law - the first black to hold the position in the organization's 72-year history.

The organization is one of the pillars of the American legal establishment whose past presidents include former secretaries of state Dean Rusk and William Rogers.

In recent years, the international law society has broadened to include blacks, young people and women. This change, said Ferguson, "is one of the more attractive features of the society, given its origin and its developemnt, and it happened without any blood flowing because its members are very bright and sophisticated people."

He said the society already is deeply involved in the problems of securing human rights around the world, and that he plans to expand these activities.

At Havard, Ferguson teaches courses in international human rights and in the economic problems of developing countries - including the problems of giving them a share of the world's riches. In 1956, while teaching at Rutgers Law School, he originated the nation's first course in international human rights and in 1964, while at Howard, he conducted a major symposium on the issue.

In addition to service as ambassador to Uganda, Ferguson also served as special coordinator of relief to civilian victims of the Nigerian civil war; U.S. representative to the U.N. Economic and Social COuncil, and Deputy assistant secretary of state for African affairs.