Woody Herman, 74, a major figure in American popular music, who played and popularized a repertoire that included blues, be-bop, swing and Stravinsky while heading his own big band for more than half a century, died yesterday in a hospital in Los Angeles.

Mr. Herman, who had been suffering from heart and lung problems for months, died of cardiopulmonary arrest in the intensive care unit of Cedars-Sinai Medical Center.

A native of Milwaukee and a child veteran of vaudeville, Mr. Herman, who sang and played the clarinet and saxophone, displayed the managerial acumen and musical talent needed to thrive at the height of the Big Band Era and to survive its swift decline.

Known for their energetic musicianship and the throbbing excitement they generated, Mr. Herman's bands, known collectively as "The Thundering Herd," kept going by changing tunes and tones with the times. They were credited, for example, with blending bop and rock.

They also remained loyal to Mr. Herman's musical roots as the leader in the 1930s of "The Band that Plays the Blues," and initiated new audiences into the delights of old sounds.

Through the decades, scores of musicians filled the chairs of Mr. Herman's ensembles, and many of those he chose, trained and led went on to noted careers of their own, including Stan Getz, Red Norvo and Zoot Sims.

In recent years, Mr. Herman had maintained a grueling schedule of nightly performances at high schools, colleges and jazz festivals.

"He loved it," his manager, Tom Cassidy, said last night, and "he needed the money."

Although at his peak, in 1945-46, Mr. Herman was earning more than $1 million a year, he was described earlier this year as broke. His Hollywood home was auctioned by the Internal Revenue Service to collect part of a $1.6 million tax bill.

After the sale, Mr. Herman had stayed in the house as a tenant, but fell behind in the rent. Friends helped him pay back rent last month and staved off his eviction.

Woodrow Charles Herman was born May 16, 1913, to parents who encouraged his early bent toward show business. Billed as the "Boy Wonder" at the age of 6, he was singing and tap-dancing at theaters around his Milwaukee home.

His early earnings went for a clarinet. A saxophone followed. While still a teen-ager, he went to Texas with a touring band.

After one term back home studying music at Marquette University, he left with a band from San Francisco. Other jobs followed, before he joined the Isham Jones band. When it broke up, in 1936, he formed his own band, specializing in blues. "Woodchoppers' Ball" was its first record hit, in 1939.

The band gained increasing fame in the late 1930s and early '40s, in ballrooms, on records and on radio. Mr. Herman was being called the major bandleader of his time. He had a gold record, "Laura." In Carnegie Hall in 1946, the band played "Ebony Concerto", specially written for the group by Igor Stravinsky.

Mr. Herman suddenly abandoned his career in 1947 after touring imposed family strains. In a few months, he returned to work, but the Big Band Era was ending.

He last played March 23 at a Minnesota high school.

His wife of 46 years, Charlotte, died in 1982. Their daughter, Ingrid Herman Reese, survives.