Changyi City, Weifang city in charge of county-level city. It is located in the northwest of Shandong Peninsula, the downstream of Weifang River, the bank of Laizhou Bay, between 36°25 '-37°08' north latitude, 119°13 '-119°37' east longitude, and Laizhou City and Pingdu City in the east with Jiaolai River as the boundary, south adjacent to Gaomi City, west adjacent to Weifang Fangzi District, Hanting District, Laizhou Bay in the north. It belongs to the total area of the city of 1627.5 square kilometers. As of 2016, Changyi has jurisdiction over 3 subdistricts and 6 towns. According to the seventh census data, as of 0:00 on November 1, 2020, the permanent resident population of Changyi was 564,501.

Changyi City belongs to the Bohai economic Circle and is one of the coastal cities designated by The State Council for opening to the outside world. It is known as the hometown of Silk, the hometown of overseas Chinese and the hometown of bromine and salt in China. It has been awarded the honorary titles of "North China Green Seedling Base", "China Textile Industry Base", "China microfiber Industry Base", "Top 100 Counties and Cities of China's small and medium-sized Cities with comprehensive strength", "Top 100 Counties and cities of China's small and medium-sized cities with the most investment potential". In October 2018, Changyi City was selected as one of the "Top 100 Counties of Comprehensive Strength", one of the top 100 counties and cities of investment potential, one of the top 100 counties and cities of green development, one of the top 100 counties and cities of scientific and technological innovation, and one of the top 100 counties and cities of new urbanization quality. On October 8, 2019, it was named as the Top 100 counties and cities of National Comprehensive Strength in 2019, the Top 100 counties and cities of National Green Development in 2019, and the top 100 counties and cities of National Science and technology innovation in 2019. In 2020, Shandong Province will be a pre-pilot city of four-star new smart city construction and a national civilized city.

In 2020, Changyi achieved a regional production value of 45.04 billion yuan, an increase of 2% over the previous year. Based on the registered population, the per capita GDP reached 77,121 yuan, an increase of 2.3 percent. The value added of the primary industry was 4.919 billion yuan, up by 2.4%; The added value of the secondary industry was 18.763 billion yuan, up by 1.8%; The value added of the tertiary industry was 21.358 billion yuan, up by 2.1%.

In October 2021, it was selected into the "2021 Top 100 Counties and Cities of China Smart Cities" list