Recently, many research have focused on the development of 3D paper-based microfluidic analytical devices(3D-μPADs) due to its unique advantages in multi-step reactions and in vitro diagnostics. However, the traditional 3D-μPADs fabrication has limitations, such as complex assembly, limited scope of application. Here, we propose a new approach to the modular 3D-μPADs based on 3D printing. During production, the microfluidic channel and the structure for assembly between modules were directly printed on the paper using a digital light processing(DLP) printer. Then 3D-μPADs was formed by assembling each module through the interface. In order to achieve different functions, four basic assembly methods including stacked, embedded ,rotary, sliding and sliding are proposed. Bone marrow stem cells (BMSCs) were inoculated in the culture zone of 3D-μPADs, and cell viability, cell proliferation analysis were carried out, and the results indicated that the 3D-μPADs can be better applied in biomedical applications. In addition, modular 3D-μPADs was combined with basic circuit components, and using conductive ink as medium, it can serve as a modular microfluidic circuits. These results demonstrate the potential of modular 3D-μPADs in both biological and circuit field.