Middletown station is an at-grade station on the Blue Line and Green Line of the San Diego Trolley system. It is located along the Surf Line right of way at West Palm Street, in the Middletown neighborhood of San Diego, which includes a variety of medium-density housing within blocks of the station. The station offers a connection to San Diego International Airport via a shuttle stop one block away from this station.

This station opened on June 16, 1996, as part of the North/South Line (later renamed the Blue Line) extension to Old Town Transit Center. The station was closed from May 21 through August 2012 for renovations as part of the Trolley Renewal Project.

There are four tracks, two for the trolley station and two passing tracks for commuter, intercity, and BNSF freight service.

Side platform, doors will open on the right
Northbound	←  Blue Line toward UTC (Washington Street) ←  Green Line toward El Cajon (Washington Street)
Southbound	→  Blue Line toward San Ysidro (County Center/Little Italy) → →  Green Line toward 12th & Imperial (County Center/Little Italy) →
Side platform, doors will open on the right
Northbound	← Coaster does not stop here ← Pacific Surfliner does not stop here
Southbound	→ Coaster does not stop here → → Pacific Surfliner does not stop here →

San Diego International Airport is accessible from this station. In July 2015, the airport added a stop near this station to buses that operate between the terminals and the airport's rental car center. Passengers board the shuttle at specially marked bus shelters the corner of Admiral Boland Way and West Palm Street, which is about 900 feet (270 m) southwest of the station along West Palm Street.

• List of San Diego Trolley stations