The BMW M3 is a high-performance version of the BMW 3 Series, developed by BMW's in-house motorsport division, BMW M GmbH. M3 models have been produced for every generation of 3 Series since the E30 M3 was introduced in 1986.

The initial model was available in a coupé body style, with a convertible body style added soon after. M3 Sedans were available during the E36 (1994–1999) and E90 (2008–2012) generations. Since 2014, the coupé and convertible models have been rebranded as the 4 Series range, making the high-performance variant the M4, so that generation of 3 Series saw the M3 produced only as a sedan. In 2020, the M3 was produced as an estate (Touring) for the first time, alongside the sedan.

Upgrades over the regular 3 Series models include engines, handling, brakes, aerodynamics, lightweight materials and various interior upgrades. The M3's biggest contribution to both driver safety and the performance industry is BMW's continual development of their limited-slip differential, which mathematically maximizes torque and grip without compromising handling. The M3's most notable implementation of technology came in 1992 when the E36 M3 was outfitted with the SMG-I gearbox. When they fitted the E46 M3 with the SMG-II gearbox, it officially took the title as the fastest shifting gear box in the world. A carbon fiber air box was developed for the E46 M3 CSL, and it worked by creating a vortex of air that could constantly maintain maximum air induction pressure to maximize throttle response.