According to Kyodo News, the Chinese report says senior North Korean leaders should be detained in camps where they can be monitored and prevented from directing further military operations or taking part in actions that could be damaging to China's interests.
The report suggests "foreign forces" could be involved in an incident that leads to the collapse of internal controls in North Korea, resulting in millions of refugees trying to flee. The only route to safety for most would be into China.
Chinese authorities intend to question new arrivals, determine their identities and turn away any considered dangerous or undesirable.
"This only underlines that all the countries with a stake in the stability of northeast Asia need to be talking to each other," a visiting scholar at the Meiji Institute for Global Affairs, Jun Okumura, told the Daily Telegraph.
"What we have learned from the collapse of other dictatorships - the Soviet Union, Muammar Gaddafi's Libya - is that the more totalitarian the regime, the harder and faster it falls.
"This is why we need contingency plans, and I am sure the US and South Korea have extensive plans, but the release of Chinese measures is new.
Okumura believed the timing of the leak of the study was significant, as China could have been expected to have had similar plans for the past 20 years as North Korea teetered on the edge of implosion.
The release of the study comes days after Beijing issued a thinly veiled warning to Pyongyang, before an expected nuclear test, that China would "by no means allow war or chaos to occur on our doorstep".
China, North Korea's sole remaining significant supporter, also refused to export any crude oil to it in the first three months of the year.
