Soroun Suot, 42, was arrested while driving his white Toyota truck on Highway 359 from Sa Kaew to Khao Hin Sorn.
Police said the suspect confessed to receiving the pork shipment from a Cambodian contact at the border in Aranyaprathet district.
The contact asked him to deliver the pork to a retailer in Bangkok for a payment of 5,000 baht, police said.
The retailer usually picked up shipments of smuggled pork at a filling station, they added.
The suspect was charged under the Customs Act and Animal Epidemics Act and sent for interrogation at Muang Sa Kaew Police Station.
Packaging for the smuggled meat showed it was imported from Russia as well as Brazil.
Russia suffered a serious outbreak of African Swine Fever (ASF) last year, while Brazil has also confirmed the presence of ASF.
The viral disease poses no risk to human health but can decimate swine farms as it is highly transmissible and leads to high rates of death among herds.
In January last year, Thailand became the last country in mainland Southeast Asia to confirm the presence of ASF, when the virus was discovered at a slaughterhouse in Nakhon Pathom.
The smuggled pork discovered on Tuesday was sent to Sa Kaew Provincial Livestock Office for hygienic disposal.
Last year, the Swine Raisers Association of Thailand warned that rampant pork smuggling threatened to ruin the Thai pig industry.