Abstract: The paper proposed a kind of improved dynamic bandwidth allocation(DBA) algorithm which was applicable to EPON system of mining area based on analyzing the particularity of EPON system of mining area and the shortcomings of traditional DBA algorithm.It analyzed implementation process of the algorithm in details.The experiment result showed that the algorithm realizes the function of DBA based on service-oriented as well as compromises the fairness of allocation,and guarantees the time delay requests of different priority businesses.