The Pinal County Sheriff's Office say 34-year-old Melisah Havens of San Tan Valley reported shooting her 35-year-old husband Friday night.
When deputies arrived, they found the man, whose name has not been released, with gunshot wounds to the chest and right hand.
Sheriff Paul Babeu says Havens said her husband had taken her car keys to go get milk.
Officials say the victim was transported by air ambulance to a Phoenix area trauma hospital where he immediately went into surgery. He is listed in critical but stable condition.
Havens was charged with aggravated assault.
It is not known if she had an attorney.