Abstract: There are various bubble generation methods which can produce bulk nanobubbles with different sizes and different number concentrations. However, the polydispersity of bubble size and the intrinsic difference of number concentration are inconvenient to the performance research and efficiency comparison of bulk nanobubbles, and it is also not conducive to the standardization and industrialization of nanobubble technology. Therefore, the size control and number concentration adjustment for the bulk nanobubbles are very important. The technologies for controlling the size and number concentration of the bulk nanobubbles in recent years were summarized and comprehensively evaluated. The advantages and disadvantages of size control methods such as cyclic homogenization, microfluidic technology and membrane technology, and number concentration control methods such as freeze-thaw removal method and ultrasonication reduction method were analyzed and compared. All methods were evaluated in terms of controllability, equipment dependence, process difficulty, scalability and cost, and new understandings and ideas for the regulation of nanobubble size and concentration were proposed combined with the published research results. It helped to deeply understand the size effect of the nanobubbles and extra stabilization mechanism and provide new ideas for the quantitative analysis and applications of bulk nanobubbles, especially for the nanobubble size-related properties, effects and applications.