主要从事地衣型真菌的分类及系统发育研究，重点研究对象有担子地衣，蜈蚣衣科及黄烛衣科的类群，涵盖青藏高原及海岸海岛等区域；参与国家自然科学基金7余项，参编专著5本，在国内外发表论文30余篇，其中SCI源刊论文20余篇（第一作者10余篇）。

代表性学术论文:

Liu D, Hur JS. 2019. Revision of the lichen genus Phaeophyscia and allied atranorin absent taxa (Physciaceae) in South Korea. Microorganisms 7(8):E242.

Liu D, Wang LS, Wang XY, Maekawa N, Hur JS. 2019. Sulzbacheromyces sinensis, an unexpected basidiolichen, was newly discovered from Korean peninsula and Philippines, with a phylogenetic reconstruction of genus Sulzbacheromyces. Mycobiology 47 (2): 191-199.

Liu D, Wang LS, Wang XY, Hur JS. 2019. Two new species of the genus Candelariella from China and Korea. Mycobiology 47(1):40-49.

Liu D, Goffinet B, Wang XY, Shi HX, Yang MX, Li LJ, Yin AC, Wang LS. 2018. Another lineage of basidiolichen in China, the genera Dictyonema and Lichenomphalia (Agaricales: Hygrophoraceae). Mycosystema, 37(7), 849-864.

Liu D, Goffinet B, Ertz D, De Kesel A, Wang XY, Hur JS, Shi HX, Zhang YY, Yang MX, Wang LS. 2018. Circumscription and phylogeny of the Lepidostromatales (lichenized Basidiomycota) following discovery of new species from China and Africa. Mycologia, 109(5), 730-748.