Yanjun Cai devoted to the researches of paleo-climatological and paleo-environmental changes recorded by the speleothem, and the stratigraphy and U-series dating of cave sediments.
The major achievements are attested by more than 110 papers (75 papers in SCI peer-reviewed journals, including 9 coauthored papers in Nature, Science, PNAS and Nature Geoscience, with a total citation of 10200 (Google Scholar). The H-index is 41. He won the second prize of National Natural Science Award in 2016 (No.3), and for three times, the outstanding achievements have been recognized as "Ten advances in Science in China".