He is best known for his failure to defend Guangzhou (Canton) from British forces during the First Opium War, and for signing the treaties of Kulja and Aigun with the Russian Empire in 1851 and 1858 respectively.
In 1821, after the Daoguang Emperor came to the throne, Yishan, then a fourth-grade noble was recruited to serve as a third-class imperial guard (三等侍衛) in the Forbidden City.
He helped them train recurits Between 1821 and 1838, he held the following appointments, among others: lingdui dachen (領隊大臣) of Da'erbahatai (塔爾巴哈台; an administrative region in present-day Xinjiang); deputy dutong (都統; commander) of the Bordered Blue Banner Han Forces; canzan dachen (參贊大臣) of Ili (伊犁; an area within Xinjiang).
During his time in Canton Yishan repeatedly sent lies and misinformation to the Daoguang emperor, making it seem that the Qing forces were stronger than the British.
However, he was released in mid-1843 and promoted to second class imperial guard (二等侍衛) and acting banshi dachen (辦事大臣) of Khotan (an area within Xinjiang).
During the Second Opium War (1857–1860), Nikolay Muravyov-Amursky approached Yishan and offered to provide Russian assistance to the Qing Empire against the British and French, in return for redefining the Sino–Russian border along the Amur and Ussuri rivers.
The Xianfeng Emperor was enraged by the territorial losses to the Russians, so he dismissed Yishan from his office as General of Heilongjiang, despite the latter's attempts to explain himself.