Firefighters were called to Sir John Graham Court in Larbert at around 8.30pm tonight to tackle the blaze.
Police and the ambulance service were also called to the scene but it is not believed there have been any casualties, a service spokeswoman said.
Six fire engines attended the incident and streets in the area were closed while the fire was brought under control.
The complex contains 19 flats and bungalows housing people over the age of 60.
Police and fire personnel on the scene within minutes.
The cross was then sealed off, from Stirling Road to Dundarroch Street, as firefighters tackled the blaze.
One resident in the Larbert area said: "It looks pretty serious, there is a large police presence at the scene and it looks bad."
Fellow resident, Ross Spalding , speaking on his Twitter account said: "Larbert Cross is mobbed with police, ambulance and fire engines. Never seen so many in my life."