Monday's reports say authorities discovered the baby at Sharjah airport when it showed up on an X-ray scan of the bag.
Carry-on luggage is typically scanned at Emirati airports on arrival, after passengers have their passports stamped.
The Gulf News says the baby boy had no passport, visa or other documents allowing him entry to the UAE.
The paper and The National daily are quoting police as saying the unidentified parents put the child's life at risk with the scheme.
The case is being handed over to prosecutors. Sharjah officials did not immediately respond to a request for comment