Henry Sears, 69, an investment banker, farmer and yachtsman who organized the syndicate that built the yacht Columbia, which sucessfully defended the Americas Cup in 1958, died of cancer March 23 at his home in Chestertown, Md.

Mr. Sears, who was born in Boston, attended Yale University. About 1940, he bought property in Chestertown where he raised corn, wheat and soybeans. He also had a farm in Albany, Ga. During World War II, he served in the Navy and commanded a destroyer escort in the Pacific.

He founded Henry Sears & Co., a venture capital firm in New York City, and remained active in it until 1972, when he retired. He maintained a home in Greenwich, Conn., until 1969, when he moved to Chestertown permanently.

Mr. Sears was a former commodore of the New York Yacht Club. He was the first recipient of the Nathanael Greene Herreshoff Trophy of the U.S. Yacht Racing Union.

He also was a trustee of the Johns Hopkins University Medical Center, the New York Zoological Society, the American Museum of Natural History and the Kent School in Kent County, Md.

Survivors include his wife, Mary Pouch Sears of Chestertown; a son, Dr. Henry F., of Philadelphia; a stepson, Peter Smithers of Greenwich; two sisters, Mrs. Henry Cabot Lodge of Beverly, Mass., and Jean Alexander of Bernardsville, N.J., and three grandsons.