Abstract: PAPR reduction for OFDM system is studied with dummy subcarrier technology and its low complexity algorithm is proposed in this paper. By deep insight into the process of dummy subcarrier technology， a simplification algorithm of which is obtained. The operation process is reduced to the level of OFDM system subcarrier number. Simulation results show that: When the number and position of real subcarrier not changed， the three distribution of real subcarrier have the same effect to the PAPR performance of OFDM， which could be improved in a certain extent by adding the number of dummy subcarrier and iterative number. As there is no side information， the system would be more reliable and robust.