Water-jet guided laser processing technology is the frontier of laser cutting application.It has advantages in the high-precision cutting of silicon wafer,gemstone,ceramic and other materials,and effectively reduces the thermal damage and slag residue of materials.The coupling alignment of infrared laser beam and microwater beam is the key technology.In order to ensure the coupling effect of microbeam fiber and laser beam,a high-precision three-dimensional coupling alignment adjustment mechanism is designed in the paper,which mainly consists of a quasi-straight focus light path system,a microhole CCD observation system,a two-dimensional microdisplacement platform,and a coupling device.The key technology of coplanar adjustment of laser focal plane and microbeam starting end(nozzle element) and alignment of laser beam and nozzle element are studied.The technology method of realizing two alignment by screen crossover is put forward in the paper.The experiments show that the microbeam coupling laser has stable length and good quality,and can achieve high efficiency and high precision cutting of silicon substrate wafers and other materials.