The Typhoons were dispatched from RAF Coningsby in Lincolnshire following the alert involving a civilian aircraft with three crew.
The Romanian plane was escorted to Birmingham International Airport, where the runway was closed for half an hour.
A spokesman said the response was routine and part of the RAF's air defence role to protect UK airspace.
One plane from Dublin was diverted to East Midlands Airport while the runway was closed.
The Saab 340 plane travelling from Bucharest landed in Birmingham at about 07:30 GMT.
The Typhoons were dispatched on a "quick reaction alert", which is used to intercept unidentified aircraft because they cannot be identified any other way.
This can be when the plane is not communicating with air traffic control, there is no flight path filed, or the plane is not transmitting a recognisable radar code for surveillance.
A Voyager aircraft from Brize Norton in Oxfordshire was also dispatched to respond to the alert.
A Birmingham Airport spokeswoman said: "We can confirm that a private Saab 340 aircraft inbound from Bucharest to Birmingham and carrying three crew encountered communication difficulties during a flight earlier today.
"In accordance with normal operating procedures the aircraft was intercepted by military jets on arrival into UK airspace and was escorted up to its scheduled arrival into Birmingham."
According to Ministry of Defence figures, there were quick reaction alerts on 12 days in 2015. Eight were in response to Russian aircraft and four were to investigate other planes.
RAF jets intercepted a Romanian plane after the aircraft lost communications, the Ministry of Defence has said.