The head of the country's tax agency, Jose David Cabello, said the chain had inconsistencies in its accounts.
The 115 branches in Venezuela were closed from Thursday to Saturday.
Venezuela's President Hugo Chavez is a fierce US critic and last month was at the heart of tit-for-tat US-Latin American diplomatic expulsions.
Since winning elections 10 years ago, Mr Chavez has increased taxes and often temporarily shuts firms accused of failing to pay.
The government recently temporarily closed the offices of Pepsi, which is operated by a local consortium. More...