This was reported by the radio station France Info on Wednesday, citing the public prosecutor's office.
The fire largely destroyed the Church of the Assumption in a suburb of Saint-Omer on Monday night.
The bell tower and the vaulted roof of the 19th century church collapsed. The act caused grief and outrage in France.
According to the public prosecutor's office, the perpetrator has numerous previous convictions and recently served a lengthy prison sentence for theft and wilful damage to property. He had also previously been involved in arson attacks on religious institutions.
The man is still in police custody.
After the fire, investigators found signs of burglary at the church. The suspect is said to have smashed a church window to gain access to the church.
The church, built in the neo-Gothic style, was last extensively renovated in 2018.
Attacks on churches have become more frequent in France in recent years.
There have also been repeated arsons.
The French Ministry of the Interior registered almost 1,000 anti-Christian hate crimes in 2023.
90 per cent of these incidents were directed against churches and cemeteries.