The drug dealer, Shakeel Ahamed, was arrested at the Katunayake International airport last night after he arrived in the country from Karachi, Lankan police said.
The arrest was made in connection with the recovery of 152 kilograms of heroine in two raids carried out by police and customs in July and August.
Ahamed is one of the main suspects in the drug racket, police said.
Ahamed is under detention order for further investigation, police spokesman SSP Ajith Rohana said.