This paper analyzed the trends and perceptions of the colonial Joseon media about the 'Korean genocide' that occurred during the Great Kanto Earthquake (Great Kanto Earthquake) in Japan on September 1, 1923. After the Kanto Great Earthquake, rumors such as Koreans rioting, poisoning wells, and rape were rampant, and more than 6,000 people were slaughtered. At the time of the Kanto Great Earthquake, the massacre of Koreans was ‘forbidden’ in colonial Joseon. Koreans who witnessed the massacre of Koreans in the Kanto Great Earthquake felt terrible, but after returning, they were subject to the colonial rule's surveillance. Therefore, the massacre of Koreans in the Kanto Great Earthquake was thoroughly controlled. However, at the end of September, the expression “the massacre of Koreans” was carefully reported along with reports of the massacre of the vigilante group and related to the trial, and it was covered more widely in articles such as related gossip articles and editorials. The analysis is as follows. First, reports related to the massacre of Koreans after the Kanto Great Earthquake were carefully reported with nuances that could recognize them rather than direct expressions. However, the media reported enough that readers who read reports related to the massacre could recognize this. Second, reports of trials related to the Korean genocide have been reported since October. This was published with a premise or partial report on a local Japanese article. The trial report began with the handling of Captain Amakas’ case of the Osgi massacre, but gradually, reports related to the Korean genocide expanded. Third, the fact-finding of the Korean genocide reported on activities in foreign countries such as Japan and the United States rather than colonial Joseon. Such reports on the fact-finding of the Korean genocide can be said to be close to the situation in which it is not possible to conduct systematic activities for fact-finding in colonial Joseon.