Lita Annenberg Hazen, a major philanthropist in medical research whose interests encompassed art, music and education, died on Monday at Mount Sinai Hospital in Manhattan. She was 86 and lived in Manhattan.

Her death was caused by complications from lung cancer, a grandson, Nicholas Polsky, said.

Mrs. Hazen had what her daughter, Cynthia Hazen Polsky, called "a great passion for family" and took a personal interest in the activities she supported. She was a friend of most of the scientists whose institutions she helped, and although she was rarely seen at the glittering social events favored by her peers, she had an active social life centered on the arts and science community.

"Medical discoveries were the most exciting and important things that she could imagine, and I don't remember her ever thinking differently or anything that competed with that," Mrs. Polsky said. "She always envisioned that someone would have a better answer."

The Lita Annenberg Hazen Charitable Trust played an important part in numerous medical and scientific programs on both coasts and made significant contributions to cultural institutions, including the Metropolitan Museum of Art, the Museum of Modern Art, the National Gallery and the Metropolitan Opera.

The Cold Spring Harbor Laboratory on Long Island was one of Mrs. Hazen's principal interests. Hazen Tower, a building at the laboratory, commemorates her participation as a founding donor of its Neuroscience Center.

"Lita Hazen was a wonderful patron of pure science, who enjoyed bright and unusual people who would say things that she wouldn't expect," said Dr. James Watson, the Nobel laureate who is director of the Cold Spring Harbor Laboratory. .

Dr. Richard A. Lerner, president of the Scripps Research Institute in La Jolla, Calif, said: "She, like Mary Lasker, was one of the great ladies of American science. These kinds of individuals play important roles in science, far beyond the simple ability to donate money. In fact, they become a magnet around which scientists gather.

Dr. Lerner added, "We are losing our 'great ladies of science,' " and he noted that with their death and with no such new individuals on the horizon, "there will not be much to replace them, and a whole culture that fostered science will come to an end."

The Hazen Trust made possible the purchase of land for a science park at the institute and also financed a chair in immunochemistry. A three-building complex at the institute, to be dedicated on Oct. 15, was named in honor of Mrs. Hazen.

Mrs. Hazen was the sixth of eight children of Sadie and Moses L. Annenberg, who founded Triangle Publications and whose holdings eventually included The Philadelphia Inquirer, The Philadelphia Daily News, the Daily Racing Form, TV Guide and radio and television interests. She was one of seven sisters, all of whom donated considerable portions of their inherited wealth to public institutions. Her brother, Walter H. Annenberg, the former United States Ambassador to Great Britain, is a major benefactor of art institutions, and a sister, Enid Haupt of New York, has devoted much of her fortune to public gardens and horticultural institutions, as well as museums and libraries.

In 1963, Mrs. Hazen was a founding sponsor of the Mount Sinai School of Medicine in New York, served as a trustee of its medical center from 1976 and contributed, with her siblings, to the construction of the 33-story Annenberg Building at the center, devoted to medical care, education and research. She also provided support for a neuroendocrinology laboratory at the Mount Sinai Medical Center that was named after her and, from 1979 to 1985, a $100,000 annual award for excellence in clinical research. The award, also named for her and administered by the Mount Sinai School of Medicine, was divided between the winner and a young medical scientist chosen by the winner

The Lita Annenberg Hazen Trust, created in 1952, also established significant scholarships and professorships at Mount Sinai, including the Moses L. and Sadie C. Annenberg Professorship in Molecular Biology, the Annenberg Scholarships in Cardiology and the Lita Annenberg Hazen Professorship in Immunochemistry.

Two grants of $1 million each helped establish and finance the Neurosciences Institute and Neurosciences Research Foundation at Rockefeller University in New York. The grants enabled multidisciplinary groups of scientists from around the world to meet and discuss their work. An atrium garden at the university was named in her honor.

In 1980, she initiated a biomedical workshop program at the Aspen Institute for Humanistic Studies and a fellowship that paid for the participation of scientists, physicians and administrators. The workshops were also held at other venues, in Stockholm, Venice and at the University of California at Los Angeles and at San Francisco.

Dr. Martin Meyerson, a former president of the University of Pennsylvania who was chairman of the workshops for a decade, noted that she insured that participants ranged from Nobel laureates to junior scientists and that "she relished providing a bit of luxury to them, a good dinner, putting them up in pleasant places."

Dr. Elaine Pagels, a professor of religion at Princeton University who was a longtime friend, said: "She had a remarkable mind, and had she been born in another generation, she might well have done something herself. She understood what research was about, even in its beginning and theoretical stage."

Mrs. Hazen was born in Milwaukee on Oct. 30, 1909, and attended the Calhoun School in New York. In 1936, she married Joseph H. Hazen, a lawyer, film producer, art collector and philanthropist at a double ceremony in which Mrs. Hazen's sister, Enid, was married to the investment banker Ira Haupt.

Mr. Hazen, a former vice president and director of Warner Brothers, wrote the contract between the studio and Edison Vitaphone that resulted in "The Jazz Singer," the first movie with sound. Later, he and Hal B. Wallis, the producer, became partners. Their company, Wallis-Hazen Productions, made films like "Come Back, Little Sheba," "Gunfight at the O.K. Corral" and "True Grit." During that period, the 1940's to 60's, Mrs. Hazen spent several months each year in Beverly Hills.

It was Mr. Hazen's admiration for Edward G. Robinson's collection of paintings that encouraged Mr. Hazen to become a collector and amass a considerable collection of 20th-century art, including work by Toulouse-Lautrec, Van Gogh, Modigliani, Leger, Kandinsky, Braque and Picasso. The Joseph H. Hazen Foundation still contributes to a number of arts institutions.

"My mother's interest in art developed with her marriage to my father," Mrs. Polsky said. "My father was more passionate about art but my mother also loved museums and paintings. She was particularly interested in the Impressionists."

Mrs. Hazen's trust made sizable contributions to arts institutions, particularly the Metropolitan Museum of Art. In most cases, the trust provided the funds for purchases, among them two important South Indian bronzes, a 14th-century "Yashoda and Krishna" and an 11th-century "Shiva, Parvati and their son Skanda," for the museum's Irving Galleries of South and Southeast Asian Art.

Mrs. Hazen and her husband also established the Gwynne Hazen Cherry Memorial Laboratory in Oncology and Hematology, in memory of their other daughter, at the Marion Davies Hospital, a unit of the University of California, Los Angeles, Medical Center. Mrs. Cherry died of lymphoma in 1965 at the age of 32.

Mr. Hazen died in 1994 at age 94, after 58 years of marriage. Mrs. Hazen is survived by Mrs. Polsky of Manhattan; four grandchildren; three great-grandchildren; a brother, Walter H. Annenberg of Rancho Mirage, Calif., and three sisters, Mrs. Haupt, Janet Hooker and Evelyn Hall of Manhattan.

Correction: Oct. 4, 1995

An obituary yesterday about Lita Annenberg Hazen, a leading philanthropist in medical research, misstated her age in some editions. She was 85, not 86.