David Miller, 56, died at his house on Patterdale Walk, Northampton, in the early hours of Tuesday.
Northamptonshire Police said the woman was 39 and of no fixed address.
Four others have been charged with murder: Zena Kane, 35; Ian Cuthbertson, 49; Michael Hallett, 37 and Joseph Catlin, 30, who were remanded in custody at Northampton Crown Court.
A woman has been arrested on suspicion of the murder of a man who was stabbed to death at his home.