“Certain countries regard our nation as a major competitor in the space field and spare no effort to contain and suppress us,” the agency said, adding that China had developed and was widely using satellite remote sensing, communication, navigation and positioning technologies.
The post did not identify which countries were involved in the cases or give any further details.
It said space had become a “strategic” area for geopolitical rivalry and that space assets were national assets that had to be managed and protected.
The agency said it would “strictly guard against the risk of espionage and theft of key aerospace technologies and data, and take concrete actions to strongly safeguard national security in the space field”.
It comes amid an increased focus on national security in China, with the public repeatedly warned about the threat of foreign spies, while a new counter-espionage law introduced last year expanded the definition of spying and the investigative powers of national security agencies.
Beijing has big ambitions for its space programme that include launching a crewed lunar mission by 2030 and a goal of becoming a world leader in space by 2050.
The US House Select Committee on US-China competition in December recommended efforts to try to counter Beijing’s space ambitions, including by funding programmes that are critical to outpacing China in space.