Abstract: Tail-biting convolutional codes（TBCC） eliminates the bit rate loss caused by traditional zero-tail convolutional codes， and has obvious performance advantages in short data block encoding. Combining with TBCC decoding， this paper proposes a blind frame synchronization scheme which is suitable for TBCC decoding to reduce the synchronization cost and improve the transmission efficiency of short data blocks. In this scheme， the node matrix is constructed by TBCC check matrix constraint， and then the real measure of each bit is accumulated as the synchronization measure criterion， and the correct synchronization position is identified while the decoding is completed. The simulation results show that for short data block blind synchronization， the scheme based on soft decision to calculate the real measurement has obvious performance advantages compared with hard decision， and is close to the performance of ideal synchronization under high SNR.