This research proposes a new application of the transform domain cyclic shift keing (TD/CCSK), which is one method of the spread spectrum. In this thesis, we applied the TD/CCSK system in the urban multipath channel and studied the performance of this system. The CCSK system was introduced, then we proposed the model for the urban multipath channel. Since the urban channel is a multipath channel, the computer simulation in this thesis was done first to the TD/CCSK in multipath channel. The performance of the system was based on the bit error rate for all cases. After we verified that the system was successfully working in the multipath channel, we applied this system to the urban multipath channel. Thus, the performance of this system in the urban multipath channel was studied and compared to the theoretical performance of the same system. By looking at all the simulation results, we can say that the TD/CCSK system is a good solution for the urban multipath channel.