Li dabbled in music and briefly studied law to please his parents, but ultimately decided to pursue fashion. Upon receivinga scholarship to Central Saint Martins in 2007, Li moved to London to study fashion. During his education, Li felt pigeonholedby its rigorous program. After an internship under English designer Gareth Pugh which failed to interest him, Li withdrew from the institution and moved to Belgium to intern under fashion designer Raf Simons. Following his experience described as"working in a creative kitchen", he launched his eponymous label in 2010.
Li's first collection "Zero Hour", released in 2010, was shown through a short film in collaboration with filmmaker and photographer Scott Trindle, in which articles of clothing were cut and repaired in varying degrees, which he saw as an act of "subtle rebellion".He proceeded to release three more collections before his Fall/Winter 2013 Paris debut women's collection, a show dubbed "phenomenal" by Vogue. In 2014, he was shortlisted for the LVMH prize. CLCC SA, a Luxembourg fashion fund who had also funded Raf Simons, made investments in Yang Li in 2015. Li debuted his menswear line in January 2016 for Paris Fashion Week. In 2017, he launched his collaboration label SAMIZDAT.
Li's work has attracted a number of highly influential stockists, including SSENSE, Farfetch, Dover Street Market, and LUISAVIAROMA.