The decision by the Federal Supreme Court shows the strong influence of Islamic law in the Emirates despite its international appeal in which foreign residents greatly outnumber the local population.
The court made the ruling earlier this month in the case of a man who left cuts and bruises on his wife and adult daughter after a beating.
It says the man was guilty of harming the women but noted that Islamic codes allow for "discipline" if no marks are left. It also says children who have reached "adulthood" - approximately puberty - cannot be struck.
The ruling was reported Monday in the Abu Dhabi-based newspaper The National.