The disclosure provides a method and device for implementing Viterbi decoding. The method comprises the following steps: calculating branch path measurement values of received code words and reference code words; parallel accumulating the branch path measurement values and measurement values corresponding to states to obtain accumulated values according to a state transition diagram, selecting a maximum accumulated value as a new measurement value of a next state, and saving all survival path selection results until data for decoding ends; and starting traceback from a final state to obtain decoded data according to the survival path selection results. In the disclosure, by modifying the traditional serial or serial-parallel mixed mode for calculating accumulated path measurement values to a multi-path fully-parallel calculation mode, the throughput rate of the system data is improved, and the decoding delay is merely in us level. In the disclosure, the traditional mode of sliding window traceback is also changed, traceback whose depth is tow times of the encoding length is only once, but the second section traceback data in the traceback depth is only valid. The accumulated values and state measurement values needn't to be stored, the method is simple and efficient, and the performance of the system is also improved.