Many of the people staying at the Bruzgi warehouse were previously living in camps near the border, waiting for an opportunity to cross into the EU, before Belarusian authorities cleared them.
Reuters footage showed the migrants holding banners reading "We are human" while they chanted "We can’t go back to Iraq".
"We need European help, help us, take us to any country. We cannot back up, we’re not safe," said one of the protesting migrants.
Another migrant from Kurdistan said the political and economical situation in his country was not good, adding people leave Iraq to lead a "better life" in Europe.
The migrants said they would stay in the Belarus warehouse and wait before they would be allowed to enter the European Union.