The Boeing 737 Next Generation, commonly abbreviated Boeing 737NG,3 is the name given to the −600, -700, -800 and -900 series of Boeing 737 airliners. It is the third generation derived from the 737, and follows the series 737 Classic (−300/-400/-500), which began production in the 1980s.

They are short- and medium-range narrow-body jet aircraft. Produced since 1996 by Boeing Commercial Airplanes, the 737NG series includes four variants with capacity for between 110 and 210 passengers.

As of the end of December 2017, a total of 6,658 737NG aircraft have been delivered, with more than 7,000 ordered. -600 and -900 have already been completed. The main competition for the 737NG is Airbus’ Airbus A320 family.

Improved models with new engines under development, such as the 737 MAX or the Airbus A320neo, will eventually replace the 737NG. As of November 30, 2019, a total of 7,092 Boeing 737NG aircraft have been ordered, of which 7,046 have been delivered, with remaining orders for the -700, -800 and -900ER variants. Boeing stopped assembling passenger 737NG in 2019, but made final deliveries in January 2020. It is succeeded by the fourth-generation Boeing 737 MAX, introduced in 2017.