Anti-Western conspiracies are frequently used by Governments to strengthen their power. We investigate the impact of conspiracy thinking on expectations of collusion among indi-viduals in Russia and China. For this purpose, we conduct a novel laboratory experiment to measure expectations of collusion and several survey items related to conspiracy thinking. Our survey results indicate that anti-Western conspiracy thinking is widespread in both countries and correlates with distrust. We find a significant effect of anti-Western conspir-acy thinking in China: Anti-Western conspiracy thinking correlates with lower expecta-tions of collusion. We explain this result by stronger in-group feeling emanating from the anti-Western sentiment. Our paper provides a first step in analyzing the economic implica-tions of conspiracy thinking for society.