Fawzi Kanaan, who runs a small, unnamed travel agency in Caracas, arrived in Venezuela in 1986, fleeing the civil war in Lebanon.
"I have nothing to do with Iran or Hezbollah. I don’t deal with politics at all," he said.
"I have been to Iran only once in 1976, just for one night. That was more than 42 years ago."
But the US describes Kanaan as a "Hezbollah supporter" and "significant provider of financial support to Hezbollah".
Washington froze his US assets and accuses him of facilitating trips for Hezbollah members, offering financial backing to Hezbollah, planning terrorist attacks and receiving training in Iran.
"This is a travel agency. I sell tickets to anyone who knocks at my door," Kanaan said.
"I don't ask them about their political orientation or what they plan to do on their trip."
Life savings
Kanaan's passports show that he has travelled in and out of the US a number of times. He now hopes to appeal against the decision in order to get access to what he says are his life savings deposited in a US bank account.
Venezuela says the accusations are false and are part of a US campaign against the government of Hugo Chavez, the Venezuelan president and a vocal critic of the US.
Venezuela, unlike the US, does not classify Hezbollah as a terrorist organisation.
Nicolas Maduro, the Venezuelan foreign minister, said: "If the US treasury department wanted to freeze any assets of a terrorist, they should freeze the accounts and assets of George Bush [the US president] who is responsible for the death of over a million Iraqis."
Ghazi Nasr Allah, a second Venezuelan citizen, has also been accused by the US of backing Hezbollah through a local Shia centre.
He denies the accusation and says the centre is used for prayers.