A seventh person, a woman, was taken to an Akron hospital in critical condition, said Rick Walters, an investigator with the Stark County Coroner's Office.
Joyce Hodous, who lives three houses down the street, said she was awakened about 4 a.m. by yelling.
"There were children screaming to get out, 'Please, help me!"' she said. Firefighters were already at the scene, she said.
Two adults and a child pulled from the first floor died at the house, coroner's chief investigator Harry Campbell said. The three others were pronounced dead at hospitals.
The children are believed to range in age from 2 months to 10 years, Campbell said.
The home apparently had no smoke detectors, officials said.
Canton is 50 miles south of Cleveland in northeastern Ohio.