They were arrested at the Kunming International Airport in Yunnan on September 7. They had flown in from Kolkatta.
They were found in possession of 18 kg of cannabis, concealed in their food packets and laptop bags.
Official sources said Indian officials were granted consular access on September 21.
“We are trying to ascertain the facts,” an official in the Indian embassy told IANS.
Drugs peddling is a serious offence in China with punishments ranging from life-term in prison and death penalty.
In July, a Colombian model was sentenced to 15 years in jail for drug smuggling in China.