Studies on social perception reveal that on many dimensions, smiling individuals are perceived more positively in comparison with non-smiling individuals. The experiment carried out in seven countries (China, Germany, Iran, Norway, Poland, USA, and the Republic of South Africa) showed that in some cultures, smiling individuals may be perceived less favorably than non-smiling individuals. We compared ratings of intelligence made by participants viewing photos of smiling and non-smiling people. The results showed that smiling individuals were perceived as more intelligent in Germany and in China; smiling individuals were perceived as less intelligent than the (same) non-smiling individuals in Iran. We suggest that the obtained effects can be explained by the cultural diversity within the dimension of uncertainty avoidance described in the GLOBE (Global Leadership and Organizational Behavior Effectiveness) project by House, Hanges, Javidan, Dorfman, and Gupta.