The Boulton Paul P.120 was a research aircraft designed and produced by the British aircraft manufacturer Boulton Paul.
It was the last aircraft designed by the Boulton Paul Company to be flown.
The P.120 was developed to investigate the aerodynamic properties of the delta wing configuration.
Performing its maiden flight on 6 August 1952, the sole aircraft conducted a series of test flights from RAF Boscombe Down.
The P.120 was very similar to the earlier Boulton Paul P.111, a tailless experimental aircraft, but principally differed by having a horizontal tail plane as well as its fixed wingtips.
The sole aircraft was lost in a non-fatal incident after encountering severe flutter, the test pilot, Ben Gunn, safely ejection seat from the aircraft in the first ejection from a delta wing aircraft.
While plans were made to rebuilt the P.111 into a second P.120, these were not deemed cost efficient and as a result no further activity with the type occurred.