LI, Di is an observer. He was trained in Nuclear physics and observational astronomy. He established a novel technique to solve the temperature distribution of interstellar dust, (co-)discovered interstellar oxygen as well as other molecules, named the HI-narrow self-absorption (HINSA) technique, which recently enabled the first HINSA Zeeman measurement that was featured on Nature's cover. As FAST’s chief scientists, he led FAST’s first pulsar, first FRB discoveries, and one of the top 10 scientific achievements in China in year 2021. He served in various advisory roles, such as the SKA, ATNF, Breakthrough Listen, etc.