The trials against the two have been held behind closed doors and their cases have caused international outrage.
According to the court, Michael Spavor has shared Chinese state secrets with foreign powers.
No verdict has been handed down for ex-diplomat Kovrig yet.
Canadian Prime Minister Justin Trudeau has previously demanded that both be released by China.
He has called both the arrest and the time they spent in captivity "unacceptable".
According to the Canadian president, China's detention of the two men is a political hostage-taking.
The arrest of Kovrig and Spavor took place in connection with a diplomatic crisis flaring up between China and Canada. Meng Wanzhou, daughter of the founder of the Chinese technology company Huawei, was arrested in Canada as a result of a US arrest warrant. China claims that the detention of diplomats has nothing to do with the crisis.