Micro-droplets are widely used in the fields of drug controlled release,virus detection,synthetic of particulate materials,catalysts and so on due to their small size,large surface area,high speed,high throughput,uniform size,closed system,internal stability and other characteristics.The emergence and development of microfluidics technology provide a new platform for the generation and precise manipulation of size-controlled microdroplets with different structures and functional characteristics.The fundamentals,generation and manipulation of droplet-based microfluidics technology are introduced.Similarities and differences of droplets'conventional preparation methods and droplet-based microfluidics technology are compared and analyzed.Finally,the applications of droplet-based microfluidics for the synthesis of functional materials,bio-medicine and design of food structure etc.are comprehensively presented.In addition,the potential value and development direction of drop-based microfluidics are discussed and forecasted.