Liu's stain (劉氏染色法) is a staining technique used to stain animal cells. It is an improved staining based on Romanowsky stain, and was introduced by professor Chen-Hui Liu(劉禎輝), faculty of National Taiwan University, in 1953. The method sees a wide variety of usage in Taiwan. Comparing to other staining methods, Liu's stain is relatively fast, taking no more than 3 minutes to complete the process. In pathology, Liu's stain is primarily used to distinguish blood cells, but it can also apply on vaginal discharge, sputum, and pus as a simple stain.