A two-dimensional axisymmetric finite element model for fiber bending was established. The fiber bending performance was analyzed by finite element method. The fiber bending loss, the effective mode field area and the splice loss were calculated respectively. The multi-objective orthogonal optimization was combined with gray relational analysis method in the design for fiber bending performance which was carried out taking the bending loss and splice loss as objective functions, taking the distance b from the core to the trench, the width of trench c, the depth of trench Δt and the radius of air holes r as design variables. The results show that the bending loss of optimized fiber decreases from 0.127 8 dB/m to 1.749 8×10-4 dB/m, the effective mode field area of optimized fiber decreases from 94.741 μm2 to 82.37 μm2, the splice loss of optimized fiber reduces from 0.174 3 dB to 5.805×10-4 dB. Compared with the standard single-mode fiber, it is found that the effective mode area of the proposed fiber decreases from 209.21 μm2 to 82.3 μm2 with the bend radius of 3 mm and the splice loss decreases from 7.535 8 dB to 5.805×10-4 dB. The proposed fiber can also ensure the transmission quality of the system in the case of small bending radius.