Conn-Selmer is an American musical instrument manufacturer headquartered in Elkhart, Indiana, and is the largest band instrument maker in the United States. The company was formed in 2003 when Steinway Musical Instruments merged United Musical Instruments with The Selmer Company's instrument manufacturing operations, and it expanded further in 2004 with the acquisition of the Leblanc Company. Production is centered at U.S. facilities in Elkhart, Indiana; Eastlake, Ohio; and Monroe, North Carolina.

The company designs and manufactures brass, woodwind, and percussion instruments under a portfolio of long-established brands, including Vincent Bach, C.G. Conn, King, Holton, Selmer (USA), Armstrong, Leblanc, Ludwig, Musser, and Scherl & Roth. Its catalog spans student through professional-level trumpets, trombones, French horns, clarinets, saxophones, flutes, concert and marching percussion, timpani, and orchestral strings. Conn-Selmer also serves as the North American distributor for Henri Selmer Paris woodwinds and Yanagisawa saxophones.

The brand's heritage draws from some of the oldest names in American band instrument making — C.G. Conn dates to 1875, Ludwig to 1909, and Vincent Bach to the early 20th century — and the company is heavily tied to school band and orchestral programs as well as professional symphonic and jazz players. Notable Conn-Selmer family models include the Bach Stradivarius trumpet line, King 2B and 3B trombones, Conn 8D French horn, and Ludwig Black Beauty snare drums.

Conn-Selmer has 1 product cataloged on Equipboard, including Alto Saxophones.