Abdul Hameed Bugti was given the capital punishment for carrying out a bomb blast in front of the Pakistan Industrial Development Corporation house in November, 2005 in which four security guards were killed and 21 others injured.
The bomb was planted in a car parked near the PIDC house by Bugti who is said to belong to the Baluchistan Liberation Army.
Two other persons, Abdul Jabbar and Mangla Khan, were also arrested in the case with the former being released for lack of evidence.
"The court has passed its sentence after hearing out both the defence and prosecution and examining all the evidence," said Munawar Ahmed, prosecution lawyer.
Many militants linked to different outlawed Islamist militant groups are still awaiting sentencing despite being arrested for terrorist activities.