Royal Air Force Molesworth or more simply RAF Molesworth is a Royal Air Force station located near Molesworth, Cambridgeshire, England with a history dating back to 1917.

Its runway and flight line facilities were closed in 1973 and demolished. New facilities were constructed to support ground-launched cruise missile operations in the early 1980s. It was one of the two British bases to house cruise missiles and a focus for protests. It is now a non-flying facility under the control of the United States Air Force (USAF), and is one of two Royal Air Force (RAF) stations in Cambridgeshire currently used by the United States Air Forces in Europe (USAFE). Molesworth, RAF Alconbury and RAF Upwood were considered the "Tri-Base Area" due to their close geographic proximity and interdependency until RAF Upwood closed in late 2012.

RAF Alconbury and RAF Molesworth were the last Second World War era Eighth Air Force airfields in the United Kingdom that were still actively in use and controlled by the United States Air Force. It was from Molesworth on 4 July 1942 that the first USAAF Eighth Air Force mission was flown over Nazi-occupied territory.

Today the base is home to the Joint Intelligence Operations Center Europe Analytic Center, and a number of units from the 423rd Air Base Group.