To provide the pseudo noise PN code phase synchronization circuit by which identification between a synchronization state and an asynchronization state is facilitated and phase synchronization at a high speed data rate is attained.

Ich/Qch complex base band signals 1a, 1b and PN codes 3a, 3b to shift a channel phase are given to correlation sections 4a, 4b. The correlation sections 4a, 4b integrate correlation value of the signals 1a, 1b and the PN codes 3a, 3b to provide outputs of correlation values 5a, 5b. A multiplier section 8 multiplies components of the same phases in the correlation values 5a, 5b to extend a dynamic range of the correlation value and a phase detection section 6 detects a phase difference between a phase at which the correlation value is maximum and a current phase and the phase difference is given to a PN code generating section 2 as a phase shift control signal 7. The PN code generating section 2 shifts the phase of the PN code so that the phase difference becomes zero.