The Woodstock Fire/Rescue District said the crash happened just after 2 p.m. at North Jefferson Street and East Judd Street.
Woodstock firefighters and police officers responded to the crash and found a man, who fire officials say is elderly, suffering from serious injuries.
The man was airlifted to Advocate Condell Medical Center in Libertyville with serious, but non-life-threatening injuries.
The man's small dog was pronounced dead on the scene. The driver involved in the crash did not report any injuries.
Railroad traffic on the Union Pacific line was shut down and remained closed until at least 4 p.m.
The Woodstock Police Department is investigating the crash. Further information was not immediately available.