Police said Chan Srichan, a resident of Moo 3 village in Tambon Nong Khaem, was run over at 6.30am on Nong Muang-Khok Samrong Road not far from her home.
Pickup driver Sommai Wongsuwan, 45, told police he was overtaking another vehicle and did not see Chan until it was too late.
He was taken into custody pending further investigation.