The BMW 5 Series is a mid-size / executive car manufactured by BMW since 1972. The car, now in its sixth generation, is sold in sedan and touring body styles. It is BMW's second best-selling model after the 3-Series but represents about 50% of the company's profits.

On January 29, 2008, the 5 millionth 5 Series was manufactured, a 530d Saloon in Carbon Black Metallic.

The 5 Series got its name by being the fifth of the "new series" cars after the V-8 and Isetta era. The preceding models were the 700, the "New Class", the "New Six" 2500/2800/Bavaria and the CS. The 5 Series was intended to replace the older New Six sedans.

The first generation's body was styled by Marcello Gandini, based on the Bertone 1970 BMW Garmisch 2002ti Geneva show car. Gandini also did the Fiat 132 and Alfa Romeo Alfetta, two other cars that have a similar design.

There have been six generations of the 5 Series to date. To differentiate between them, they are referred to by their unique chassis numbers (EXX or FXX).

The 5 Series began the BMW tradition of being named with a three-digit number. The first digit (5 in this case) represents the model, and the following two digits (usually) represent the size of the engine in decilitres, which is the main distinguishing difference. Additional letters or words may be added to the end of the three-digit number to define the fuel type (petrol or diesel), engine or transmission details, and the body style. The 'i' originally stood for (fuel) 'injection'.