The atomization characteristics of group-hole nozzle were numerically investigated with the revised spray model. The results show that due to the compromise effect of micro-orifice from the reduction of nozzle diameter and jet interaction from the overlapping part of spray, the spray of parallel group-hole nozzle is similar to that of the single nozzle, both of which have good axial symmetry. However, the spray penetration of the parallel group-hole nozzle is slightly lower than that of single nozzle with the equivalent hole area, and is significantly larger than that of single nozzle with the same hole diameter. With the increase of the hole spacing and inclined angle, the jet interaction decreases, which results in the reduction of the spray penetration and SMR of the group-hole nozzle. Meanwhile, the spray axial symmetry of group-hole nozzle is finally lost. Compared to the converging group-hole nozzle, it is faster for the diverging group-hole nozzle to lose the spray axial symmetry and decrease the spray penetration.