Since the end of 19th century, two-phase hydrocyclone has been applied widely, owing to its high efficiency, small footprint and simple operation. However, two-phase hydrocyclone cannot meet the requirement of production, especially the demand of three-phase separation in oil-gas field development, such as separating associated gas and drilling fluid treatment, which accelerated the three-phase hydrocyclone development. From the beginning of 1990s, different types of three-phase hydrocyclone have been developed with little application and research. Through a brief introduction of three-phase hydrocyclone type and present technical situation, this paper analyzed the deficiencies of different three-phase hydrocyclone and came up with suggestions for improvement. (C) 2015 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.