An optical information recording medium reproducing device (1) reproduces information from a super-resolution optical information recording medium (100a) having the information stored therein by positioning, according to a random pattern system, a plurality of recording marks including a recording mark shorter than a resolution limit of an optical system. This reproducing device (1) performs test readings for measuring indexes each relating to a reproduction quality of the super-resolution optical information recording medium (100a) by emitting laser light onto a storage surface of the super-resolution optical information recording medium (100a), while changing a reproduction laser power from a predetermined initial value, and based on the indexes measured, sets a reproduction laser power for reproducing the information. Thus, since the reproduction laser power for reproducing the information stored in the super-resolution optical information recording medium (100a) is determined based on the test readings results, a favorable reproduction quality can be obtained.