Owing to based on the nonlinear effect, the all-optical encryption scheme can only be applied to encrypt signal wave optical signal，in order to solve the problem that recent all-optical scheme can not be applied to encrypt multi-wave signal simulatanously, an all-optical encryption system scheme which can simultaneously encrypt multi-wave optical signals is proposed. This scheme is based on pockels effect of LiNbO3 waveguide and achieves signals encrypting operation by interference of coherent optical signals and keys. Because the difference of modulated phase shift of different wavelength through the same external electric field in LiNbO3 waveguide is very small, so, this scheme can be used to encrypt multi-wave signals simultaneously. The simulation of encrypting operation of 8×10 Gbps multe-wave signals whose interval of wavelength is 0.8 nm has been realized, the code type is NRZ with rise and fall time of 10ps, the BER of the encrypted output is smaller than 4.30×10－86. And the Q factor of the encrypted output is larger than 21.51. It is verified that this all-optical encryption scheme can achieve encrypting operation for multi-wave input signals within 400 nm by theoretic analyzing and simulative experiment. Moreover, when the wavelegth range of multi-wave signal is small than 78 nm, the operation of all-optical enctyption can improve the extinction ratio of input signals. Theoretic analyzing and simulative experiment comfirm the feasibility and effectiveness of this multi-wave all-optical encryption system.