The drugs were discovered late Tuesday morning when a security scan of Li Huanhuan's luggage showed irregularities.
Customs officers asked to check her bag manually but did not find any suspicious items until they slit the interior base of the luggage and discovered a false bottom containing three bundles of crystal meth, weighing 1kg each.
The drugs are worth at least 10 million baht, according to authorities.
Ms Li, who travelled from Shenzhen on a Thai AirAsia flight, denied any knowledge of the drugs. She claimed she had planned to spend her holidays in Thailand and booked a room at a hotel on Petchaburi Road in Bangkok. A friend asked her to carry a travel bag and someone would collect it when she arrived in the country, she said.
Ms Li was charged with possessing a category one drug and carrying it via Thailand for sale.