In 1826, the sixth year of the reign of the Daoguang Emperor, Yang joined an army that marched north to Xinjiang to suppress a rebellion led by Altishahri warlord Jahangir Khoja.
When the First Opium War broke out (from the Chinese perspective) in June 1840, Qing Special Commissioners Lin Zexu and Deng Tingzhen were resolute in their opposition to the British but their successor Qishan instead sought compromise.
He appointed "Qishan Pacifier of the Rebellious" (Jìngnì, 靖逆) and made Yang Fang and Long Wen (隆文) ministerial attaches (Cānzàn Dàchén, 參贊大臣).
Yang Fang disagreed with the terms of the Convention of Chuenpi signed by Qishan and British Plenipotentiary Charles Elliot in January 1841 and on March 5, he arrived in Canton with a thousand troops from Hunan Province.
Aged 71 and so deaf that communication with him had to be in writing, Fang led Chinese troops in an attack at the Second Battle of Canton, which ended when further negotiations between the two sides temporarily terminated hostilities.