Soft power is the ability to obtain what one wants through co-option and attrection. It can be contrasted with hard power, which is the use of coercion and payment. The primary currencies of soft power are an actor's values, culture, policies and institutions. The competitiveness structures of the cities in China are so unbalanced. Their rapid economic growth wins worldwide attention, whereas the growth of soft power lags behinds severely. Beijing and Shanghai, the benchmark for Chinese cities, play an exemplary role in the growth of soft power. The authors make a comparative analysis in order to make out the present situation of Beijing and Shanghai's soft power in global context. Based on the evaluation index system of metropolis' soft power developed by Zhuang in 2009, the paper evaluates the soft power of Beijing, Shanghai, New York, London, Paris and Tokyo from the perspectives of urban culture, international communications, urban innovation, public administration and quality of living. The findings are as follows. First, New York City emerges as the number one city in terms of comprehensive soft power, followed by Paris, London, Tokyo, Beijing and Shanghai. Second, according to their overall scores, the six international metropolises are grouped into 4 levels. New York City, which scores 100, is far ahead of the other 5 metropolises; while Shanghai only scores 53 and is ranked last. Paris, London and Tokyo belong to the same level, and the scores of them are 91, 88 and 85 respectively. The score of Beijing, which is 67, is higher than that of Shanghai's, however, it is far lower than other 4 metropolises. Furthermore, Paris, which is ranked the second place, wins in the urban innovation, followed by Tokyo. Third-ranked London wins in the urban culture category, while Tokyo takes the fourth place primarily due to its excellent performance in life quality. Though Beijing and Shanghai lag behind other 4 metropolises, they have good points in several indices, such as index of city safety, index of health, and so forth. Finally, the paper explores why there is huge gap between the soft power of the cities' in China and that of the other Metropolises'.