While one man sat in the cabin of the loader, a second man was tasked with cutting the tree, while the 69-year-old stood in the loader's bucket, hoisted higher up alongside the tree.
But something went wrong as the crew set to cutting down the sizeable pine, prompting the loader to tip over and sending the 69-year-old crashing to the ground, the local Piteå-Tidningen (PT) newspaper reported.
The man was rushed to hospital, but his injuries were so severe that he died before he arrived.
"We don't know why he died. Whether it was because he ended up under the loader or the tree or if he died due to the fall," police spokesperson Cathrine Hedqvist told the paper.
The driver of the loader also was also injured slightly when the vehicle tipped.
Police at first classified the incident was a workplace accident, but later learned the men were acting on their own accord and weren't a part of a professional tree-felling operation.