Police made the discovery during a roadside breath test at Triabunna, about 86km north-east of Hobart, last night.
Inside, a cardboard box was located that contained $1 million in cash.
Police allege the cash is profits from the sale of illicit drugs, and the man was subsequently arrested.
The 57-year-old from Mayfield was charged with dealing with property suspected of being the proceeds of crime.
The offence carries a maximum sentence of two years’ imprisonment.