<p>This study used Chinese cultural symbols and the names of various domestic Chinese ethnic groups to represent the common in-group, and Western cultural symbols and Western ethnic group names to represent the common out-group. Through three studies, we investigated differences in Chinese multiethnic university students’ manifestations of the container metaphor, intergroup evaluations, and cooperative behavior towards domestic and foreign ethnic groups. Study 1, employing a spatial Stroop paradigm, found that university students tended to place Chinese cultural symbols inside a container and Western cultural symbols outside. This result indicates that university students can establish identification with the superordinate identity of the Chinese nation through cognitive schemas of Chinese cultural symbols. Study 2, using a priming Stroop paradigm, revealed that university students held more positive intergroup evaluations towards domestic Chinese ethnic groups and relatively negative intergroup evaluations towards Western ethnic groups. Study 3, utilizing the Prisoner’s Dilemma Game, demonstrated that university students’ cooperation rate with members of domestic Chinese ethnic groups was significantly higher than with members of Western ethnic groups. These findings not only enrich the Common Ingroup Identity Model but also provide a novel pathway for fostering positive identification with the Chinese nation by establishing a superordinate group identity.</p>