As of 2021, China's economy has continued to grow, and some cities have shown a relatively fast development speed.

The following are the top 10 fastest growing cities based on a comprehensive assessment of different indicators (such as GDP growth rate, fixed asset investment, industrial upgrading speed, etc.):

1. Shenzhen - As a special economic zone and a center for scientific and technological innovation, Shenzhen's high-tech industry has developed rapidly.

2. Hangzhou - Relying on Internet companies such as Alibaba, Hangzhou has made remarkable achievements in the field of digital economy.

3. Chengdu - As an economic center in the western region, Chengdu has rapid development in the fields of electronic information, biomedicine, etc.

4. Chongqing - As a municipality directly under the Central Government, Chongqing has a diversified industrial system and a huge domestic demand market.

5. Wuhan - An important city in the central region, Wuhan has outstanding performance in industries such as optoelectronics information and automobile manufacturing.

6. Guangzhou - An economic center in southern China, Guangzhou has rapid development in both manufacturing and modern service industries.

7. Nanjing - A famous historical and cultural city, Nanjing has developed rapidly in software and service outsourcing, smart hardware and other fields.

8. Suzhou - Suzhou, close to Shanghai, is famous for its advanced manufacturing industry and the concentration of foreign-funded enterprises.

9. Tianjin - An economic center in the north, Tianjin has advantages in port logistics, high-end manufacturing and other aspects.

10. Qingdao - An economic powerhouse on the Shandong Peninsula, Qingdao has distinctive developments in marine technology, beer manufacturing and other fields.

It should be noted that the speed of urban development is affected by many factors, such as policy support, geographical location, industrial foundation, talent concentration, etc., so the above rankings may change over time and data updates. In addition, different evaluation criteria and data sources may also lead to different conclusions.