Henry M. Wriston, president emeritus of Brown University whose parttime government service included a reorganization of the U.S. diplomatic corps, died yesterday in a New York City Hospital following a long illness. He was 88.

Dr. Wriston was born in Laramie, Wyo., and was reared in Massachusetts. He earned bachelor's and master's degrees at Wesleyan University in Middlebury, Conn., and later taught there. In 1922, he earned a doctorate in diplomatic history at Harvard University. Three years later, he became president of Lawrence College in Appleton, Wis. In 1937, he was named president of Brown, a post he held until 1955, when he was appointed president emeritus.

He did not confine himself to scholarship or university administration any more than the world of affairs ignored academia. He was a member of The Establishment - that amorphous group of leaders in various fields who influence the course of events whether or not they hold positions in government.

In 1954, John Foster Dulles, President Eisenhower's first secretary of state, named Dr. Wriston chairman of a "public committee on personel" to reorganize the State Department and its Foreign Service.

At the time, many State Department officials whose duties concerned foreign policy were under the civil service system. They were not required to serve abroad. Foreign Service officers - the department's professional diplomats - rarely were required to serve in the United States.

With the United States assuming the role of a global power in World War II and its aftermath, It was felt that both groups should be combined into one service, the better to manage the nation's diplomacy. The Hoover commission on the reorganization of the federal government recommended that this step be taken in the late 1940s.

But it was not until Dr. Wriston's committee did its work that this came about. The "Wriston Report," as it was called, recommended that "home" service and "foreign" service personnel be merged "where their official functions converge."

Moreover, the report recommended that the merger be carried out within a period of two years.

The result was that the Foreign Service tripled in size by 1957 to 3,689 positions.All Foreign Service personnel were obligated to serve at home as well as abroad.

The changes were not carried out without opposition. Many civil service employes of the State Department were unwilling to meet the Foreign Service obligation of serving abroad and the different standards for promotion in the Foreign Service. Many Foreign Service officers resented the expansion of what they regarded as an elite group by "lateral" transfers of State Department employes who would enter the Foreign Service without having to take written examinations.

State Department officials say today that the Wriston reforms have made the Foreign Service more efficient. Moreover, they say, the reforms have helped to open the ranks of the diplomatic service to what one has called "Main Street, America."

Dr. Wriston's other government service included the chairmanship of the Commission on National Goals, a privately funded group appointed by President Eisenhower. Among its recommendations were calls for continued aid to underdeveloped countries and the end of racial discrimination so that the nation could make use of the talents of black citizens.

Dr. Wriston also served as president of the private but influential Council on Foreign Relations, as a trustee of the Carnegie Endowment for International Peace, as a public governor of the New York Stock Exchange, and as president of the American Colleges and of the Association of American Universities.

He was the recipient of 34 honorary degrees and the author of numerous books and articles.

"Security," he once said, is "the most corrosive word in the dark lexicon of our time. Life is an adventure and the only security is the grave. This is not a soft world. Most of us have cruel hardships. Protection from hardship is a denial of experience."

Dr. Wriston's first wife, the former Ruth Colton Bigelow, died more than 30 years ago. They had two children, Walter B. Wriston, chairman of the board of Citibank in New York, and Barbara Wriston, the head of museum education at the Art Institute of Chicago.

In 1947, Dr. Wriston married the former Marguerite Woodworth, who also survives him. They had lived in New York in recent years.