Micro-PIV is a new technique for measuring the velocity fieldof a micro-scale flow in recent years. It is a kind of full field,instantaneous and quantitative measurement method that combines traditionalPIV with microscopic technology. Comparing with the traditional PIV, thebasic principle is the same, but it is remarkably different in seedingselection, image acquisition and processing. Micro-PIV breaks through thelimitation of the traditional measurement methods employed in micro-scalefluid mechanics, and extends the studies based on some limitedinformation aboutflow rate and friction characters to the flow structure of the wholefielddirectly with high resolution and precision. In the presentarticle, the development of Micro-PIV in recent years is summarized andanalysed, its differences from the traditional PIV and the processingtechnologies are discussed, the Micro-PIV application in science andengineering is reviewed and its progress is forecasted.