The sinkhole was filled with water after a burse water pipe led to the road falling in.
However, the water has now been cleared and these pictures - sent in to The Yorkshire Post by John Carlisle - show just how large the hole is.
The road is expected to be closed for around 48 hours.
National Highways said: "The A64 in North Yorkshire is closed eastbound between the A169 (Malton, Norton-on-Derwent) and the B1429 (Willerby, Staxton), and westbound between the B1429 and the B1428 (Scagglethorpe) due to a burst water main which has resulted in a large depression in the road surface.
"Yorkshire Water have been in attendance to assist in repairing the damaged water main, and our contractors are also on scene to repair the road surface damage.
"The road is expected to be closed for at least 48 hours for emergency repairs to take place."