Police said Tuesday 41-year-old Vidmantas Sungaila registered 7.27 grams per litre of alcohol in his blood repeatedly on different devices when he was pulled over for driving his truck down the centre of a two-lane highway 100 kilometres from the capital, Vilnius, on Saturday.
Lithuania's legal limit is 0.4 grams per litre.
"This guy should have been lying dead, but he was still driving. It must be an unofficial national record," Saulius Skvernelis, the director of the national police traffic control service, told the AP. "He was of high spirits and grinning the whole time he was questioned."
Medical experts say anything above 3.5 grams per litre of alcohol in the blood is lethal for most people.
"A person this intoxicated should be in an intensive care unit, not behind the wheel," said Tautvydas Zikaras, head of the dependence illness centre in the country's second-largest city, Kaunas. Zikaras said he had never heard or read of someone being so drunk.
Sungaila, who was slapped with a fine equivalent to about £600 and the loss of his licence for up to three years, told police he had been drinking the night before and tried to freshen up by downing a pint of beer for breakfast.
Lithuania has one of the worst road safety records in the European Union. Last year, 760 people died in traffic accidents in this country of 3.5 million residents. Most were alcohol-related.