McHenry police said officers responded to the Hampton Inn at 1555 South Illinois Route 31 just after midnight Saturday.
Police believe Colin M. Foster, a 28-year-old McHenry man, suddenly stabbed a 48-year-old man with a knife multiple times. Foster also battered a 38-year-old man, who did not suffer any knife wounds, police said.
All three men involved were staying at the hotel, but police do not believe Foster has any connection to those he allegedly attacked.
The stabbing victim, who suffered serious but non-life-threatening injuries, was transported to Advocate Condell Medical Center in Libertyville for treatment.
Foster was charged with one count of attempted murder and two counts of aggravated battery with great bodily harm, police said. He was transported to the McHenry County Jail to await court proceedings.
Police are investigating and asked anyone with information to contact them at 815-363-2599 or call the McHenry Police Tip line at 815-363-2124 to remain anonymous.
Further information was not immediately available.