The 54 year old from Tari was taken into the Boroko cells this morning, after the victim, 43, reported the matter.
The attack took place at their residence near the 5 mile ridge area on Thursday (January 11th).
Police said the suspect was not happy with her husband, a retired policeman, after he stopped giving her money during the festive season last year.
The 62 year old man also from Tari had married the two women traditionally but according to police reports was not keeping his monetary obligation to his first wife.