A Canadian man who allegedly concealed about 12 kilograms of cocaine in the lining of two suitcases has been intercepted at Sydney airport, authorities say.

The 19-year-old man arrived at Sydney's international airport from Canada on Monday.

When customs officers examined his baggage they allegedly found two packages concealed within the lining of two suitcases.

Tests revealed the packages contained cocaine, Customs said, adding that forensic testing was being carried out to determine its exact purity and quantity.

The man was referred to the Australian Federal Police and charged with importing a commercial quantity of a border controlled drug.

He was due to face Sydney's Central Local Court on Tuesday afternoon.

The maximum penalty for this offence is life imprisonment and/or a $825,000 fine.