Abstract: According to the 3D integral preform which is used for multidirectional heteromorphic shaped composite parts, the preform sample with typical pulling in and adding in yarn structure was designed and prepared based on the 2.5D woven with warp-stuffer preform. Computed tomography (Micro-CT) was used to observe the morphological changes of the yarn cross-section and the distribution of yarn orientation in each system. The squeezed state of the pulled out and added in yarn changes along the thickness direction of the preform, and the cross-section shape of the pulled out and added in yarn are changed from an ellipse to a trapezoid, and then to a triangle. When the warp yarns are pulled out and added in, the cross-section of the weft yarns in contact with them change. Combining the practical loading condition of the composite parts, 5 kinds of composites with pulling out-adding in yarns were tested by three-point bending in warp direction. The results show that the retention rates of bending strength and modulus of the composites reach 82.6%-95.7% and 89.1%-97.9%, respectively. So, to meet the mechanical performance requirements of the composites, developing the 3D integral shaped braided technology of preforms is the effective approach for realizing the material/structure integrated manufacturing of complex shaped composite parts.