An elderly woman has died after being run over by a car at a church in The Gap in Brisbane's west.

The 86-year-old woman had just finished having lunch with friends in The Gap Uniting Church on Sunday afternoon when she was run over and pinned beneath a sedan leaving the car park.

The woman had sustained life-threatening injuries and ambulance paramedics tried to revive her, but she was pronounced dead at the scene, Police Inspector Steve Flori said.

"Preliminary investigations reveal that an 89-year-old driver has reversed her vehicle out of the car park," she said.

"Three elderly females have walked in front of the car and for some reason unknown at this stage, the car has lunged forward and sadly has run over one of the females.

"People that attended this function were friends of hers and obviously she has family that we have notified they are all upset and our sympathies go to those family and friends for this tragic event."

Police said they were unlikely to charge the driver.