Leonard Louis McBrowne was born January 24, 1933, in Brooklyn, New York. His father Arnold was a working drummer, and Lenny followed him into the instrument early, playing in street marching bands between the ages of twelve and fifteen while also studying bass on the side. After finishing high school in 1951, he got the kind of grounding few young drummers can claim: a full year of direct study with his idol, Max Roach — whose own career, including that mentorship, is covered in full in his JazzProfiles.com profile — and further instruction from drummer and educator Sticks Evans.

His professional start came in Pete Brown's group, which at the time featured a young Paul Bley on piano. McBrowne worked Brooklyn clubs alongside Randy Weston and Cecil Payne, then went out on the road touring with Bley's trio as far as Montreal. In 1956 he was in New York playing with clarinetist Tony Scott — four tracks on Scott's RCA Victor album The Touch of Tony Scott carry his drum credit — before relocating to California. The West Coast years put him in high company fast: engagements and recordings with Billie Holiday, Sonny Stitt, Harold Land, Benny Golson, Curtis Fuller, and Sonny Rollins all date from this period. Critics of the day, per the label copy circulating with his later reissues, hailed him and his working band as among the greatest promise for the future of West Coast jazz. He was, plainly, "a disciple of Max Roach," and reviewers of the time routinely likened the "suavely exotic tendencies" of his solo work to Chico Hamilton's.

In 1959 McBrowne formed his own group, the Four Souls, with pianist Terry Trotter, bassist Herbie Lewis, tenor saxophonist Daniel Jackson, and trumpeter Donald Sleet. Recorded between January and March 1960, Lenny McBrowne and the 4 Souls came out that year on Pacific Jazz. A second album, Eastern Lights, followed on Riverside, recorded in Los Angeles on October 13, 1960, with Jimmy Bond on bass in Herbie Lewis's chair — and produced, notably, by Cannonball Adderley. Between the two records McBrowne also cut a Riverside single, "Saudi" backed with "Even Dozen" (both tracks resurface on Eastern Lights itself), under his own name.

When the Four Souls dissolved, McBrowne went back to freelancing, and the sideman work only got deeper. He recorded across the mid-to-late 1960s with Sonny Criss, Booker Ervin — some of the drummer's most driving, aggressive playing is on Ervin's Prestige dates — Barry Harris, Teddy Edwards, Charles McPherson, and Pat Martino, and worked with vocalist Sarah Vaughan. 1970 was a Japan-heavy year for McBrowne specifically. He joined Thelonious Monk's touring quartet, alongside tenor saxophonist Paul Jeffrey and bassist Larry Ridley, for Monk's autumn tour of Japan; a live recording from the Shinjuku Koseinenkin Kaikan date on October 4, 1970, was issued in Japan the following year as Thelonious Monk in Tokyo on the Express label — a genuinely rare release, distinct from (and not to be confused with) the far better-known 1963 Columbia live album of nearly the same title, which used a different rhythm section entirely. The same year, and reunited with the same bassist, Larry Ridley, he also recorded in Japan on Helen Merrill and Teddy Wilson's Helen Sings, Teddy Swings and on the three-guitar summit Guitar Genius in Japan with Kenny Burrell, Attila Zoller, and Jim Hall — the first documented dates of his long working relationship with Burrell.

McBrowne relocated again in the early 1970s, this time to San Francisco, where he became a regular presence in guitarist Kenny Burrell's bands — appearing on Burrell's 'Round Midnight (1972), Both Feet on the Ground (1973), Up the Street, 'Round the Corner, Down the Block (1974), and Stormy Monday (1978) — alongside continuing dates with Randy Weston (Blues, 1975; Berkshire Blues, 1977) and pianist Red Garland, whose 1973 MPS session The Quota also carries his credit. His recording career effectively wound down after 1976. He died in San Francisco on October 4, 1980, at age forty-seven.

His influence outlived him in an unexpected way: avant-garde drummer Andrew Cyrille has named Willie Jones and Lenny McBrowne as his first drum teachers in Brooklyn — and it was through McBrowne and Jones that Cyrille first met Max Roach, closing a small, direct lineage running from Roach through McBrowne to the next generation.

McBrowne was a textbook hard bop drummer, shaped directly by a year of study with Max Roach: an aggressive, propulsive ride cymbal pushed ahead of the beat, driving without overwhelming the front line. What set him apart from other Roach-schooled drummers of his generation was the character of his solo playing, which contemporary critics consistently described as "suavely exotic" — a quality that drew repeated comparisons to Chico Hamilton, another drummer known for coloristic, texture-conscious soloing rather than pure power. That range made him equally credible behind Booker Ervin's hard-charging Prestige dates and inside the more chamber-like settings of Paul Bley's early quartet work or his own Four Souls records, which leaned into a cooler, West Coast-inflected hard bop.