He was also a pioneer of the modern studies of Chinese dialects and of non-Chinese languages in China.

Besides spending some years in the United States as a visiting scholar, he spent most of his academic life at Peking University.

Chao and Li Fang-kuei, he became a researcher at the Institute of History and Philology (歷史語言研究所) of Academia Sinica (then located at Nanjing).

He also served as director of the Institute of Linguistics at the Chinese Academy of Sciences until his death in 1958.

Luo also co-authored a book on the 'Phags-pa script with Cai Meibiao (Chinese: 蔡美彪).