C. Douglas Dillon, a versatile Wall Street financier who was named secretary of the Treasury by President Kennedy and ambassador to France under President Eisenhower, and was a longtime executive of the Metropolitan Museum of Art, died Friday at New York Presbyterian Hospital in Manhattan. Mr. Dillon, who lived with his wife on Jupiter Island in Hobe Sound, Fla., was 93.

Mr. Dillon was born to wealth and influence as the son of the founder of Dillon, Read & Company, an international banking house. Mr. Dillon was widely respected for his attention to detail -- he had a reputation for ferreting out inconspicuous errors in reports -- and his intellect, which his parents began shaping at an early age by enrolling Mr. Dillon in elite private schools.

Mr. Dillon is said to have been able to read quickly and to fully comprehend what he read by the time he was 4 years old. At the Pine Lodge School in Lakehurst, N.J., Mr. Dillon's schoolmates included Nelson, Laurance and John Rockefeller III. Mr. Dillon later graduated magna cum laude from Harvard and sharpened his analytical powers on Wall Street.

Strapping and strong-jawed, Mr. Dillon sometimes seemed self-effacing or even shy in public, despite his long prominence in public affairs and in business. He served over the years as chairman of the Rockefeller Foundation, president of Harvard University's board of overseers, chairman of the Brookings Institution, vice chairman of the Council on Foreign Relations, and, after his time in Paris, in high posts at the State Department.

In the business world, he rose to be chairman of Dillon, Read and of the United States and Foreign Securities Corporation, an investment company founded by his father, Clarence Dillon.

Despite his patrician roots, Douglas Dillon was only twice removed from more meager means in Poland, where his paternal grandfather was born. Mr. Dillon's grandfather, Samuel Lapowski, a Jewish immigrant from Poland, moved his family to Texas after the Civil War and began building several businesses and propelling his children to higher social strata through education. Mr. Dillon's father studied at Harvard and, at some point, changed his surname from Lapowski to Dillon, which was his mother's maiden name.

In private life, Douglas Dillon and his first wife, the former Phyllis Chess Ellsworth, amassed collections of Impressionist paintings and other works of art. His interest in art led him to be selected as a trustee of the Metropolitan Museum two decades before he became its president. He served from 1970 to 1977, when he became chairman.

In March 1983, Mr. Dillon said he planned to step down as chairman in the fall, explaining, ''My feeling is that this is quite long enough for one person to hold these offices.''

Mr. Dillon's first wife died in 1982. He is survived by two daughters from that marriage, Phyllis Dillon Collins and Joan, the Duchesse de Mouchy. Mr. Dillon is also survived by Susan Dillon, whom he married in 1983, and three grandchildren.

Mr. Dillon was a lifelong Republican who had long been active in party affairs when he was picked for the Treasury post by President Kennedy in an attempt to give an incoming administration a bipartisan cast. Kept on by President Johnson, Mr. Dillon served as secretary of the Treasury from 1961 to 1965, and his fiscal policies won wide support.

''I am a moderate Republican,'' he said as he left the cabinet, adding, ''I do not believe that there are great differences between that kind of Republicanism and the objectives'' of the Kennedy and Johnson administrations.

In his years as the secretary of Treasury, Mr. Dillon played a key part in drawing up the Trade Expansion Act of 1962, which empowered Mr. Kennedy to cut tariffs by half in the course of reciprocal negotiations. As secretary, Mr. Dillon was also instrumental in framing the Revenue Act of 1962, which mandated a 7 percent investment credit that was meant to spur industrial plant and equipment investment. He oversaw the revising and liberalizing of principles for the companies' handling of depreciation charges.

However, Mr. Dillon's influence and the weight of the Treasury dwindled near the end of his tenure when it became known that he was going to resign; he had wanted to leave government for some time. And wide notice was taken, even by his admirers, of his inability to bring about an end to the deficit in the United States' balance of payments.

After leaving his cabinet post, Mr. Dillon returned to the world of finance, where the Dillon name was a byword long before World War II, thanks to his father, who amassed a fortune at the head of Dillon, Read. The company was one of the prominent Wall Street houses that underwrote hundreds of millions of dollars worth of bonds that were floated in the United States by numerous European cities and countries after World War I.

The elder Mr. Dillon and his wife, Anne Douglass Dillon, were spending a year abroad when Clarence Douglass Dillon was born Aug. 21, 1909, in Geneva, Switzerland. The terminal ''S'' was later dropped from his middle name.

The son was brought up in New York and New Jersey. He graduated in 1927 from the Groton School and in 1931 from Harvard, where he was considered too wiry to be a member of the football team. Instead, he became its manager.

Once he graduated, he had time to acquire a seat on the New York Stock Exchange, using $185,000 that his father had staked to him for the purpose.

In 1937, after working on the stock exchange and as an investment banker, Mr. Dillon became president and a director of the United States and Foreign Securities Corporation. The next year he also became a director at Dillon, Read.

In World War II, Mr. Dillon interrupted his Wall Street career to serve in the Navy, seeing action in the Pacific. He earned the Legion of Merit and the Air Medal and rose to the rank of lieutenant commander.

In 1946, he became chairman of Dillon, Read, but he left that post, and also left the securities corporation in 1953, the year President Eisenhower chose him to be ambassador to France. The appointment was largely seen as a political spoil because Mr. Dillon, who at that time also served as a Republican state committeeman, had helped to lock in votes from New Jersey's Republican delegation for Mr. Eisenhower's bid for president. Mr. Dillon also made financial contributions to Mr. Eisenhower's campaign.

To some, Mr. Dillon was a logical choice for the Paris post since he was familiar with France, partly a result of the fact that for 20 years his family had owned the Château Haut-Brion vineyards, which produced Bordeaux wine. Initially, though, Mr. Dillon was criticized because of his crude command of French, his youth and his inexperience as a diplomat. But he quickly gained respect after he diligently studied French with a tutor and performed ably during several incidents in which the United States disagreed with the French government's policies.

In the State Department, as ambassador until 1957 and then as under secretary of State for economic affairs and as under secretary of State, Mr. Dillon was noted for analyzing problems in detached Wall Street style and then acting firmly and logically.

After leaving government, he again returned to Wall Street. But after he was elected president of the Metropolitan Museum, the museum work came to fascinate him so much that he spent most of his time at it. An avid collector of 18th- and 19th-century French paintings, Mr. Dillon also gave the museum much of the artwork that he acquired over the years and he is credited with nearly single-handedly building the museum's Chinese painting collection.

''It was his passion, which he developed out of an institutional need because it was a weakness at the Met,'' said Philippe de Montebello, the director of the Metropolitan Museum. ''He wanted the Met to be strong in all fields, so he literally adopted Chinese arts.''

The galleries were set up with money from the Dillon Fund, a small family foundation set up in 1922; and Mr. Dillon made personal contributions as well.

While he led the museum, Mr. Dillon oversaw the completion of a campaign to raise funds for new construction. It brought in $118 million. He also directed the beginning of another fund-raising campaign, intended mainly to enlarge the museum's endowment. By late 1982, the campaign was more than halfway to its goal of $150 million.

After retiring from the Met, Mr. Dillon continued to serve the museum, most recently on the acquisitions committee, which he was said to love so deeply that, during a recent illness, he read acquisitions papers from his hospital bed.

Clarence D Dillon