The invention provides a distributed storage slow disk processing method and system, a terminal and a storage medium, and the method comprises the steps: carrying out the slow disk detection of a distributed storage cluster, and screening and marking a slow disk; judging whether isolation of the marked slow disk exceeds a cluster fault domain or not; if yes, reporting a slow disk fault alarm; and if not, reporting a slow disk fault alarm and isolating the slow disk. According to the method, the detected slow disk is marked, the marked slow disk is subjected to fault domain rule judgment, whether the isolation of the marked slow disk conforms to the fault domain or not is judged, and if not, the fault alarm of the slow disk is generated only, and the slow disk is not isolated; therefore, the situation that the availability of the distributed file system is reduced due to direct isolation of the slow disk can be avoided, the fault expansion of the distributed file system is avoided, and the high availability of the distributed file system can be ensured while the adverse effect of the slow disk in the distributed file system on the system performance is solved.