The invention discloses a data access method and device and belongs to the field of computers. The data access method comprises the steps of receiving data access request with highest priority based on the priority of multiple data access requests when the detecting data access requests sent by multiple HAC through HAC-I respectively connected with the multiple HAC in each clock period, storing the received data access requests in an LMI data queue based on the types of the received data access requests, and conducting data access on SOC storage resources based on the data volume carried by target data access requests in the LMI data queue, initial addresses carried by the target data access requests and maximum data volume of SOC bus lines. The data access requests sent by the HAC through LMI are subjected to arbitration, resolution and protocol conversion, repeated resources of resolution logic and protocol conversion logic are saved, only access interfaces are provided for the LMI by the SOC bus lines, and the number of the access interface of the SOC bus lines is decreased.