The 21-year-old woman was nabbed just after she arrived on board an AirAsia flight from Hong Kong.
Due to her suspicious behaviour, a team from the Customs Department stopped her and asked to see her bag.
On inspection they found a secret compartment where a package containing the Syabu weighing about 4.8 kilogrammes was found.
It was the biggest drug bust for the department thus far this year.
Disclosing this, State Customs Director Datuk Dr Janathan Kandok said the suspect has been remanded for seven days and will be investigated under Section 39B(1) of the Dangerous Drugs Act 1952 (Act 234).
"Our initial investigation also revealed that the suspect was scheduled to be in Sabah for two days before leaving for Kuala Lumpur and thereafter to Hong Kong.
"We are still investigating whether she is a drug mule or involved in any drug syndicate to make Sabah a hub for drug trafficking activities," he said.
Dr Janathan said the department believed drug syndicates tend to use international or domestic flights to smuggle drugs like ketamine and methamphetamine.
Since 2011, he said the department had solved eight cases involving suspects of different nationalities with total seizure of drugs amounting to 42,377.60 grammes valued at RM4.16 million.
He said all the cases happened at KKIA, Tawau Airport and Sandakan Airport.
Dr Janathan said the public can channel information by contacting the department's hotline at 1-800-88-8855 or the nearest Customs office.