An experimental device for encapsulating biologically active substances was designed and fabricated based on the principle of droplets generation with orifices. Orifices were fabricated through embedding capillary instead of precision machining. Thus the parameters of orifices, such as size, depth and number, can be changed smartly. Miniaturization of the device was realized through improvement of the pressure system design, which reduces the usage amount of specimen. Cell microcapsules preparation experiment was carried out. The result showed that cell microcapsules size and size distribution varies agilely with the change of pressure and orifice diameter parameters; the device is suitable for encapsulation of biologically active substances.