The crash happened just after noon along the UP-North line in Kenosha, authorities said.
It's unclear how the man was hit by a train. He has been identified as 34-year-old Austin Raysby of Burlington, Wisconsin, Union Pacific said in a statement.
No other injuries were reported.
Authorities continue to investigate the incident.
Union Pacific released the following full statement:
We are saddened by the loss of a Union Pacific family member in Kenosha, Wisconsin, and extend our deepest sympathies to his family and the employees who worked alongside him. The incident occurred around 12:15 p.m. CT near 13th Avenue and 69th Street in Kenosha. Our emergency response team is on-site investigating the incident. No one else was hurt.