Abstract: Tubular Miura-ori (TMO) structure has attracted much attention due to its excellent folding and rich application diversity. However, its deformation theory is rarely studied. In this work, the “equivalent deformation mechanism” is proposed to study the double deformation modes of TMO. The geometry of the structure is studied by using the vector expression of the creases, and the deformation of TMO is equivalent to the change of angle to simplify the analysis of axial deformation mode. The equivalent method is applied to the bending mode to derive the mathematical relationship of the double deformation modes because the deformation mechanism of bending is similar to that of axial, and its correctness is analyzed by numerical analysis. Finally, experimental research was carried out. The consistency of numerical analysis, experiment and theoretical analysis is higher. The results show that the proposed method can efficiently and simply describe the double deformation modes of TMO, which provides theoretical value for engineering applications of TMO structures.