This research indicates the cultural significance of judging the personality of the characters from the Romance of the Three Kingdoms and explains the core values of moral behavior. In this book, I first quoted from the Book of Eastern Han and The History of the Three Kingdoms, as they relate to judging the characters' personalities, in order to explain historical methodologies used to judge the characters' personalities from the end of Han to the Three Kingdoms period. Second, I introduced three important episodes, which may be used to judge the characters' personalities: 1. Shu Ching recommended Wo Lung. 2. Tsao Tsao judged all the heroes, while he was drinking wine with Liu Bei. 3. Chao Yun judged all the heroes. The criticism of the heroes by Shu Ching followed the tradition of commending capable persons for the court in the Eastern Han period; however, Tsao Tsao and Chao Yun emphasized the characters' personalities from the local leaders. While Tsao Tsao judged the heroes, he mentioned the two Yuans and two Lius: If the person had no talent, then he could not be listed as hero. The concept was based solely on talent. While Chao Yun judged the heroes, he criticized Yuan Shao and Kungsun Tsan, as they were not loyal to their leaders and had no compassion to save the people. Therefore, Chao based his standard solely on virtues. There was depth in the description of how Chao Yun judged the heroes. He stated that during the hardships and the fighting in the Three Kingdoms period, the upright and merciful persons still upheld the universal values of morality and compassion. In researching the judgment of characters’ personalities from the Romance of the Three Kingdoms, we can identify important cultural significance.