The Louisiana State Museum has the largest collection in the world of instruments owned and played by important figures in jazz, possessing multiple examples of all the commonly used instruments: trumpet, cornet, trombone, clarinet, saxophone. Some late 19th-century instruments date from the early days of jazz, others were used by local musicians who either never left New Orleans or came back.

Notable examples of instruments in the collection are:

• Louis Armstrong Cornet and Bugle- Louis Armstrong was taught to play these when he was a resident of the Municipal Waif's Home for boys, 1913-14, sent there for shooting off a pistol on New Year's Eve. Without the encouragement of the staff, and the self-discipline and musical education he acquired there, the most important individual career in the history of jazz probably never would have happened. The objects are not only historically important, but visually distinctive. The cornet has notches in the non-detachable mouthpiece cut by the young Armstrong, in an attempt to aid his embouchure, and who later described them in print long before the instrument had come to light.
• San Jacinto Hall Sign- San Jacinto Hall was a dance hall on Dumaine Street, highly popular in the black community and the site of several recording sessions highly important to the New Orleans Revival in the 40s. It burned down in 1967, but the elaborate tin-metal sign above the entrance was saved.
• Tom Brown's Typewriter- Brown took the first Dixieland group out of New Orleans to Chicago in 1915, for a well documented engagement at Lamb's Cafe. But as the ODJB was the first to record, in 1917, it generally took credit for being the "first" jazz band. Brown angrily defended his claim to primacy for the rest of his life, with many letters pounded out on this typewriter.

The Jazz Collection has over time picked up many odds-and-ends pertaining to jazz, some of it clearly of value, some close to worthless. Much of this is not considered part of the collection proper, but is kept for reference, as study material, even possibly for future exhibit props. Much of it is ephemera, never intended to last. A jazz concert ticket, for example, has a useful lifespan of a few minutes, from the moment you buy it at the box office to the moment you hand it to the ticket taker. But fifty years later, when the performers have become legends, the stub of that ticket with the particulars printed on it can have remarkable evocative power.