The method to cool a high heat flux device is an important research direction for the heat exchanger design.Micro-channels are an effective heat exchange s～ucture both for single-phase and two-phase flow.In this paper,the heat transfer correlations of single-phase,two-phase and nanofluid in a micro-channel are discussed and analyzed.The correlations of pressure drop for single-phase and two-phase fluids are also presented.Excluding the different working fluids used in the micro-channel,the diameter and aspect ratio,shape and structure,surface roughness,internal and external factor and layout of micro-channel pipe are considered to analyze their influence on the heat transfer performance and pressure drop.Micro-channel technology applications include industry,air-conditioning,solar energy systems,heat pipe technology and computer data center cooling.Compared to the conventional heat exchangers used in these fields,a micro-channel heat sink showed a much better heat transfer coefficient and low volume,indicating that it is a good choice and has huge potential for cooling application.Finally,existing problems and future scopes are described,and drawing up design standard,experimental and simulated methods for evaluating its performance are the urgent actions which need to be carried out.This review paper serves as guidance for researchers to design and predict the performance of micro-channel heat sinks.