His father Su Chuo (蘇綽) was the key assistant for Western Wei's paramount general Yuwen Tai.
Su Wei, however, was fearful of the power that his father-in-law wielded, believing that it would eventually be a source of disaster, so for a while he fled into the mountains to be a hermit.
[1] Soon thereafter, his uncle forced him out of the mountains back into governmental service, but he still spent much of his time in Buddhist temples, reading various books.
Su, believing that Tujue authorities could be bribed, sold all of his belongings to ransom his cousin and Yuan.
[2] Emperor Wen made Su Wei the head of the examination bureau (Menxia Sheng, 門下省), one of the five main bureaus in his governmental structure,[2] and the minister of finance as well as appointing him to assist with the legal reforms of the Kaihuang Code.
[2] In 589, after Emperor Wen's forces conquered rival Chen dynasty and unified China, Su suggested that a local governmental layer, the township, be created, each with 500 households, headed by a mayor.
Li Delin, who had often opposed Su's suggestions, pointed out that this would lead to situations where multiple counties would have to share one township and create confusion as well as potential for corruption by the mayors.
In the summer of that year, he also made Su one of the heads of the executive bureau (Shangshu Sheng, 尚書省).
At that time, Su, along with Gao, Yu Qingze (虞慶則), and Emperor Wen's nephew Yang Xiong (楊雄) the Prince of Guangping, were known as the "four nobles" due to the power they wielded.
Emperor Wen had Yu and his son Yang Xiu the Prince of Shu investigate, and the accusations were found true.
By summer 594, Emperor Wen had restored Su Wei to his dukedom and again made him the head of the examination bureau.
[8] In 595, Su was accused of a lack of proper respect when accompanying Emperor Wen in sacrificing to the god of Mount Tai, and was removed, but soon restored.
[9] In 604, Emperor Wen died—a death that traditional historians, while admitting a lack of direct evidence, generally believed to be a murder ordered by his son and Yang Guang the Crown Prince.
He put seven officials in charge of the process of reviewing officials' performance and promotions—Su, along with Niu Hong, Yuwen Shu, Zhang Jin (張瑾), Yu Shiji, Pei Yun (裴蘊), and Pei Ju, and they were known collectively as the "seven nobles of officialdom."
[10] In 607, despite Su's opposition, Emperor Yang built a section of the Great Wall from Yulin to Zihe (紫河, in modern Hohhot, Inner Mongolia), employing over a million men in labor.
Su responded, "Only a person who is capable of judging what is right and wrong and what is successful and unsuccessful can be called intelligent.
Much as Su feared, while Yang Xuangan's rebellion was quickly suppressed, thereafter, there was little peace for the rest of Sui's history.
Emperor Yang's extravagant promises of promotion and reward brought reinforcements and Princess Yicheng falsely informed the khan that the Turks were under attack from the north.
Emperor Yang was displeased when someone pointed out that the Classic of History contained a chapter entitled the Song of the Five Sons[15]—a lament by the five brothers of King Taikang of Xia dynasty[16] that he lost his kingdom due to his excessive cruelty and hunting—and believed that Su was criticizing him.
When Li was subsequently defeated by Sui troops under Wang Shichong, who at that point-controlled Luoyang and was nominally supporting Emperor Yang's grandson Yang Tong as emperor, Su surrendered to Wang and was restored to the title of Duke of Pei.
[1] In 621, Wang, facing military pressure from Li Shimin, the son of Emperor Gaozu of Tang, surrendered.
Su subsequently went to the Tang capital Chang'an and sought an audience with Emperor Gaozu, and was similarly rebuked and not given an office.