The Department of Foreign Affairs said yesterday that three Australians were on death row after being convicted of narcotics offences in Asia.

Vietnam, which has some of the world's toughest anti-drug laws, last year sentenced an Australian man to death by firing squad for heroin trafficking.

Tran Van Thanh, 39, was sentenced by a Ho Chi Minh City court last year after being convicted of attempting to traffic 700g of heroin from Vietnam to Australia.

His two accomplices, both Australians of Vietnamese descent, Pham Dai Nhon and Le Thi Loan, received 16- and 20-year jail terms respectively.

Last August, 33-year-old Australian Tran Thi Hong Loan was found guilty of trafficking 881g of heroin hidden in a hairspray bottle. She was detained at Ho Chi Minh International Airport while preparing to board a flight to Sydney.

Her original death sentence was later reduced to life imprisonment.

Another Australian, Nguyen Van Chinh, 45, faces death by firing squad in Vietnam.

She was sentenced in a one-day trial in Ho Chi Minh City after spending more than two years in jail following her 2002 arrest for smuggling 1050g of heroin.

In Singapore, 24-year-old Vietnamese-Australian, Nguyen Tuong Van of Melbourne sits in death row after his conviction for smuggling 400g of heroin on his way home from Cambodia. Narcotics trafficking in Singapore usually means a mandatory sentence of death by hanging.

While three Australians are facing sentencing for drug smuggling in Cambodia's notoriously corrupt courts, 16-year-old Sydney teenager Gordon Vuong is languishing in a Phnom Penh jail for minors after his controversial conviction for trying to smuggle 2kg of heroin out of the country.