The woman was stopped by authorities as she prepared to board a Vietnam Airlines flight to Sydney late on Friday.
Local media reports security officers made the arrest after discovering illicit drugs concealed inside two jars of fish paste.
The case is being investigated.
Last December, a 71-year-old Vietnamese-Australian woman was detained after police allegedly uncovered some three kilograms of heroin hidden in 36 soap containers in her luggage.
Vietnam is reported to have among the world’s toughest drug enforcement laws, with the death penalty for those convicted of smuggling more than 600 grams of heroin or of methamphetamines.
– with other agencies