Pictures taken by shocked onlookers show the bright orange flames rise from the HGV between Romford and Dartford.
The lorry carrying a large amount of tyres burst into flames around 1pm today (August 13).(Image: ECFRS)
Firefighters are on the scene with police reporting there have been no injuries.
While the inferno burned in the anticlockwise carriageway, drivers in the opposite direction took videos of the huge blaze.
Others have captured pictures of the large pillar of smoke rising into the air from miles away.
The anticlockwise carriageway is completely closed to traffic but the road has reopened clockwise.
Lane closures are expected throughout the day, warns National Highways, with the need for road resurfacing anticipated.
There are delays of an hour in the area.
An Essex County Fire and Rescue Service spokesperson said: “We are dealing with a lorry fire on M25, clockwise between junctions 29 and 30.
“Crews from Grays (two), Basildon, Brentwood and colleagues from London Fire Brigade and Kent Fire and Rescue Service are in attendance.
“The lorry is carrying tyres, which are alight and are producing large amounts of smoke.
“The clockwise carriageway is closed and there are long delays on the anticlockwise carriageway.
“Please avoid the area if you can and take extra care if you are near the scene.”
An Essex Police spokesperson said: “The M25 is closed in both directions between junctions 29 (A127) and 31 (A13), following a lorry fire.
“We are supporting firefighters and National Highways at the scene, and the road is expected to remain closed for several hours.
“Thankfully, no injuries have been reported at the scene.
“Please check before your travel and plan your journeys accordingly.
“Check National Highways for the latest information regarding the road closure and thank you for your patience.”
