Shia LaBeouf seemingly lost his cool while in Rome ... appearing agitated with a woman sitting next to him outside a restaurant.

The controversial actor was spotted hanging out in Italy's capital earlier this week ... sitting at a table in a t-shirt and jeans and sipping out of a bottle.

Check out this video ... He's talking animatedly to this woman ... before loudly yelling "F*** off" at her.

Despite his anger, she appears relatively unfazed ... not moving a muscle while he stares her down.

Later on, the video picks up with Shia screaming in the street ... pacing around a crosswalk and yelling in a general direction. It's unclear if he's yelling at the same woman or someone else.

As you know ... Shia has had a concerning few weeks -- beginning with his arrest for battery in New Orleans last month. He was allowed to travel to Rome despite the arrest, where he was filmed walking around a hotel lobby in just his underwear.

Video of Shia in New Orleans Friday -- shortly after returning from Rome -- captured a shouting match with cops ... which ended with Shia in tears.