For the shallow tunnel of Qizishan with small net distance bias, the typical locations of the tunnel were selected to establish a fine three-dimensional model, and the tunnel construction process under different construction sequences was simulated. The effects of three different construction sequences of bias side first, bias side second and simultaneous construction on the formation deformation and structural stress were studied, which provided a basis for the determination of construction sequence. The results show that the first construction on the bias side causes the largest stratum displacement, followed by the simultaneous construction, and the last is the backward construction on the bias side. The maximum variation of the vertical and horizontal displacement of the stratum caused by the construction sequence is 15.50% and 62.50% respectively, and the maximum variation of the internal force of the supporting structure is 22.63%. Considering that the formation displacement and structural force variation caused by the change of construction sequence are within the allowable range, the on-site construction of Qizishan tunnel adopts the scheme of simultaneous tunneling of left and right lines, and the cons-truction process and monitoring data verify its rationality.