The 73-year-old close aide of former President Hu Jintao was charged with bribery, abuse of power and leaking state secrets in April.
The ruling Communist Party of China (CPC) had charged Zhou, making him the senior-most official to face trial in over three decades, capping President Xi Jinping's anti- corruption drive against "tigers and flies".
Dubbed as a security czar for holding the post of the national security chief under Hu's administration - the powerful post which enabled him to keep a tab on the CPC including its top brass.