Objective: To investigate the relationship between patriotism and nationalism, and themediating role of system-justifying beliefs between the two. Methods: A convenient sampling methodwas used to recruit a total of 1862 participants from Tianjin Normal University in two waves. Theparticipants completed the Patriotism Scale, the System Justification Scale, and the Nationalism Scale,and the mediating role of system-justifying beliefs between patriotism and nationalism was tested.Results: Patriotism was significantly positively correlated with system-justifying beliefs (r=0.562***)and nationalism (r=0.202***). System-justifying beliefs were significantly positively correlated withnationalism (r=0.327***). System-justifying beliefs played a complete mediating role between patriotismand nationalism. Conclusion: Patriotism can positively predict the level of nationalism. System-justifyingbeliefs play a complete mediating role between patriotism and nationalism.