The van detonated at the office in the Australian capital, leading to a major police response
Lobby managing director Lyle Shelton tweeted a photograph of the incident and said no staff were injured.
He said: “A vehicle has rammed our office in Canberra & exploded all staff are safe.
“I do not know the condition of the driver. Prayers appreciated.”
A man is thought to have been behind the wheel when the van ploughed into the Eternity House building at around 10.45pm local time.
The explosion destroyed the van and blew out a number of the building’s windows.
A spokesperson for the Australian Capital Territory Police confirmed the vehicle was driven towards the front of the building and said an investigation was underway.
They added: “Investigations into a vehicle fire at the Australian Christian Lobby and no one was injured inside the building.
“There are no public safety issues and ACT are seeking any witnesses to the incident.”
No arrests have been made but the alleged driver is thought to be receiving medical treatment.
It comes just two days after a suspected Islamist rammed a truck into crowds at a Christmas market in Berlin.
Twelve people died and dozens more were injured in the atrocity on Monday evening.