Sources said he was quizzed for over three hours during which he also wrote down his statement.
Perumal has also been questioned by the CBI earlier in connection with their parallel probe into the scam. The ED along with the CBI had also raided premises of his firms late last year.
Sources said the investigating teams are trying to find out if his companies acted as a front for Raja's financial dealings. The agencies are probing the money trail in the scam.
Though officials were tightlipped about the line of questioning, sources said, he was asked about financial transactions and his dealings with certain firms.
Sources said he may be questioned again. Raja, arrested by CBI in connection with the scam in 2G spectrum allocation, is in Tihar jail after the court remanded him in judicial custody.
The ED has registered a case under Prevention of Money Laundering Act (PMLA) in connection with the spectrum scam. Besides certain government employees, both the ED and the CBI have also trained their guns on corporate honchos and are in the process of questioning telecom firm officials.