The BMW S65 is a naturally aspirated V8 petrol engine which was produced from 2007 to 2013. Its main use was in the BMW M3 (where it replaced the BMW S54 straight-six engine). There is no direct replacement for the S65, since the following generation of M3 switched to a turbocharged straight-six engine (the BMW S55).

Derived from the BMW S85 V10 engine (as used in the E60 M5), the S65 shares the same basic architecture and aluminium construction. Unlike most other BMW M engines, the S65 and S85 are not related to a regular production BMW engine.[1]

The S65 won the International Engine of the Year award for the 3.0 to 4.0 L category in 2008, 2009, 2010, 2011 and 2012.[2]