Pol Maj Gen Chanthep Saesawet, Deputy Commissioner of the Narcotics Suppression Bureau told a news conference of the arrest of the six men in Thawi Watthana district.
Apart from the drugs, two cars, two motorcycles and 10 mobile phones were seized from the group, believed to be members of a Shan ethnic drug ring in Bangkok's Bang Khae district.
Police said the leader was an inmate in the southern province of Nakhon Si Thammarat who masterminded the operation from his jail cell.
According to investigators, the drugs were transferred from Chiang Rai and kept in the Bang Khae area before delivery to the southern provinces.
The men were to be paid Bt80,000 for each delivery.
Meanwhile, railway police arrested a drug dealer at Hua Hin station on a Bangkok-Butterworth express train bound for Malaysia.
Pol Maj Gen Thanang Buranond, commander of the Railway Police Division told reporters that the dealer, identified as Anan Tevasuk, was arrested with 50kg of ice valued at Bt70 million.
The suspect was under police watch on the Bangkok-Butterworth train. When it arrived at Hua Hin station in Prachup Khiri Khan, police identified themselves and asked to search his two bags. They found the drug cache in the two bags.
Mr Anan told police he was hired by a dealer in Chiang Mai to deliver the drugs to customers in Songkhla's Hat Yai district. He received Bt50,000 in return.