The accused were arrested in three separate raids on up-market apartments around the capital Kuala Lumpur on August 9. Police seized about 185 kilograms (408 pounds) of methamphetamine, according to the charges.
The suspects, including a woman from Uzbekistan and another from Iran, were charged Thursday and Friday in a Kuala Lumpur district court, said their lawyer Tania Scivetti.
No pleas were recorded on the drug trafficking charges, Scivetti said.
The next court dates are September 19 for three of the accused and October 23 for the rest. Chemist reports on the drug find are expected to be submitted and an interpreter for the Iranians found.
Malaysia has strict anti-drug laws, punishing trafficking by hanging. According to government figures, some 700 prisoners were on death row as of early last year, mostly for drug offences.
Malaysia has seen a sharp rise in the number of Iranians detained on drug trafficking charges in recent years. Several Westerners have also been arrested recently.
The Star daily cited police earlier this month as saying that the Iranians were believed to have been processing and smuggling methamphetamine for more than three months, shipping the drug into the country.
Police had been monitoring the syndicate allegedly processing the drugs for sale in Malaysia and in neighbouring countries.
The arrests in the first apartment led to the other raids. Police also seized cars, cash and jewellery, The Star said.