As the green card of a city, the city flower and city tree reflect each city’s image, character, spiritual connotation, and regional culture, which is of significant research value. At the same time, the relevant systematic researches are scarce. The status and statistical analysis of the city flowers and city trees were researched with a case study of 39 important cities in China from the perspective of using the minority to reflect the majority by referring to official information, searching periodicals, and newspapers, telephone counseling, etc. The results show that the existing problems with the selection of city flowers and city trees include without city trees in some cities, similar selection, be short of updating and addition on some old selection, unreasonable selection procedures, and so on. On the basis, selection criteria of city flower and city tree were put forward from the aspects of favorites of citizens, typical native plants, image symbol, profound historical basis, and economic benefit. Lastly, strategies for promoting the selection of city flowers and city trees were proposed. The paper contributes to the choice of city flowers and city trees in small and medium-sized cities and the change and addition of city flowers and trees in large cities of China. It benefits the theory frame of city flowers and city trees.