The propagation of spatial solitons in homeotropically aligned nematic liquid crystal is discussed by using the split-step Fourier algorithm. Applying one plane wave to generate pretilt angle in homeotropically aligned nematic liquid crystals′ and another incident beam is injected into the liquid crystal cell through the cell′s centre. Then the evolution equation of the incident beam is given. When the incident beam enters 70 μm thick liquid crystal cell, the refractive index and orientation angle of the liquid crystal in the cell are numerically calculated. At last, the incident beam propagation in 70 μm and 100 μm thick homeotropically aligned nematic liquid crystal is obtained numerically. According to the theoretical analysis, it shows that the pretilt angle in the liquid crystal can be generated by one parallel beam instead of electric field. It is also found that in the 70 μm thick liquid crystal cell, the soliton is difficult to be found. However, in 100 μm thick liquid crystal cell, it is easy not only to get the soliton but also to get the breather whose vibration cycle changes with the intensity of incident beam.