Police say a woman called for assistance when she found two males asleep in her home and another severely beaten in the basement on Saturday.
Thunder Bay Police Service officers received the call just before midnight. Paramedics took the man to Thunder Bay Regional Health Sciences Centre with severe head injuries. The man remains in intensive care.
Police say they found a 14-year-old-boy and a 20-year-old-man asleep in the home and charged both with aggravated assault.
Both appeared in court on Sunday and will remain in custody until their next court appearance.