PAPR reduction is an important issue in wireless OFDM transmission. Partial transmit sequence (PTS) is one of the distortionless methods. However, PTS requires side information on the phase rotation. This impacts not only the transmit efficiency but also the standardization process. Thus, blind detection without side information is expected as a solution to implement PTS. In the paper, simple blind detection with very low complexity is proposed. The computer simulation results indicate that the proposal gives almost the same performance as one with perfect side information by selecting a proper set of phase rotation candidates.