Maria Elvira Pinto Exposto was arrested at Kuala Lumpur airport in December 2014 carrying 1.1kg (2.4 pounds) of crystal methamphetamine.
The court accepted her argument that she had been unaware of the presence of the drugs in her luggage.
Her lawyer said she had fallen for an online romance scam and had been tricked into carrying the drugs.
Death by hanging is mandatory for drug trafficking in Malaysia.
Anyone found in possession of at least 50g (1.75 ounces) of crystal meth is considered a trafficker.