The new type of inclined web box girder with spaced arrangement can reduce the self-weight of the beam and save the construction cost. However, the global force analysis and the local transfer mechanism of this new structure need to be further deepened. For example, the analysis of its torsion and distortion effects can not be ignored in the global force analysis of the single-cable-plane cable-stayed bridge. By taking the construction process of the cantilever pouring of the girder of a single-cable-plane cable-stayed bridge as researching background, the torsion and distortion effects of the inclined web girder with spaced arrangement are analyzed with the calculation model. The results show that the stress warping coefficient and the additional deflection caused by the partial load of the near cantilever end section are larger under the action of eccentric load. The stress warping coefficient at the intersection of the web and the top and bottom plate is greater than that at other positions. The axial additional stress coefficient of the inclined web is larger and gradually increases from the top to the bottom of the inclined bar on both sides. The axial additional stress coefficient of the oblique web decreases from the section near the cantilever end to the section near the fixed end, and is reversed near the fixed end. The oblique web can transfer the upper load to the bottom plate and make a great contribution to the torsional stiffness of the box girder. The analytical results are verified by the laboratory scale-model experiment, which shows that the presented analytical method is correct. The conclusions and results can guide the construction and provide references for the similar type of cable-stayed bridge.