Hanoch Yassu of Beersheba was being held in the death of his wife, Sarah Yassu, 37, who police said was beheaded overnight while the couple's three young children slept in the next room, Ynetnews.com reported.
Hanoch Yassu, an Israel Prison Service officer, told investigators he suspected his wife was cheating on him, Ynetnews said.
Police said he had called and reported he and his wife had attempted suicide.
Police and emergency workers found his wife's headless body, and Yassu was found drunk near a detention facility where he works, officials said.
The knife believed to have been used in the killing was found in the house.
The couple's three children -- ages 2, 6 and 7 -- were found sleeping. They were not harmed.
Neighbors said there had been no indication of friction between the couple.