Tan Cheng was born in Huailai County, Dexing District. His father, Tan, served as the city-handing order at the end of Jin Dynasty, and the Mongolian army captured Xiaheshuo area. Tan led the whole county to join, was appointed as the left supervisor, and still served as the Jiaocheng county magistrate. Soon, he was given a tiger symbol to make contributions to the Marshal's House and attack Bianjing. At the age of 40, he fell ill and recommended his younger brother Tan Ziyong as his agent. Tan Ziyong died, and Tan Cheng inherited his uncle's position. Tan Cheng was smart since he was a child, and he was only 19 years old when he was appointed as Jiaocheng county magistrate. There is a rule in Jiaocheng that irrigation should be directed to Jiaocheng's fields. Guo Shuai on the north bank of Wenjiashui built a weir to monopolize water conservancy. People have been complaining about this matter for years, but it has not been properly handled. Tan Cheng persuaded people by reasoning, so that Guo Shuai burst its banks and all the people in Jiaocheng benefited. Some powerful people have seized the shortcomings of officials and committed crimes. Tan Cheng found out their names and punished them according to law. B registered his household registration years ago, and the government mostly registered with customers. When the tax was levied, all the residents fled, and the government lent money to the people, accumulating several times the interest that the people could not repay. Tan Cheng went to the imperial court to see him, and expressed his interest to Taizong Wokuotai through a written order from Lu Ye Chucun. Emperor Taizong was moved by it and ordered the exemption of tax arrears. Although the years are long, the money and goods owed by private individuals only receive double interest. Those who escape can go home and be exempted from rent and tax for three years. After the imperial edict was issued, it was convenient for both public and private. Lunzinian, a large number of registered accounts. In Tancheng, all the accounts of people who have not lived in Jiaocheng for a long time have been deleted, so that taxes can be collected on time.