To provide a storage medium control device capable of preventing retention of random access even in the intermixed state of sequential and random access.

This storage medium control device is used for a data storage device for processing based on a plurality of requests including sequential access requests and random access requests to a data storage medium. The storage medium control device 50 includes a request response delay monitoring means 51 monitoring a response delay to the request based on whether the response time to the request exceeds a specific delay allowable limit time, and request control means 58, 62 restraining the rearrangement of sequential access requests when exceeding the delay allowable limit time, and processing in the specific request order at a passing point of time upon the lapse of time.