He returned to China in 1957 after graduating from the Moscow Conservatory and was made conductor of the China Central Philharmonic and was put in charge to provide music at state and diplomatic functions such as entertaining important visitors such as Henry Kissinger on his earlier secret diplomatic missions to Beijing.
In 1979, Maestro Li joined hands with American violinist Isaac Stern to perform the violin concertos of Mozart and Brahms.
This historical musical collaboration was captured in the Academy Award-winning documentary From Mao to Mozart, which offered some of the first glimpses of a newly opening China.
In the ensuing years, Li served as a bridge between musicians from China and abroad, performing with artists such as David Oistrakh, Isaac Stern, Yehudi Menuhin, Yo-Yo Ma, Fou Tsong, Liu Shikun, Yin Chengzong and many others.
He was a tireless advocate for classical music and spent his free time lecturing on the subject of music enjoyment throughout China, presenting its beauty and sophistication with a simple and humorous delivery to university students and factory workers alike, making it appealing to the younger generation as well as the general public.