To provide a sample mounting position reading device which is capable of easily specifying a target sample container among a plurality of sample containers mounted on a tray or the like.

A sample mounting position reading device for reading mounting positions of a plurality of sample containers 4 comprises; an identification information storage part for storing identification information of specific sample containers 4; an imaging part 22 for imaging the plurality of mounted sample containers 4; a mounting position specification part for specifying mounting positions of respective sample containers 4 by decoding images of sample identification code parts of the sample containers 4 which are contained in a captured image; a comparison part for comparing identification information of the sample identification code parts which is contained in the image with the identification information stored by the identification information storage part; a sample specification part for specifying the sample container 4 having the sample identification code part corresponding to the identification information stored by the identification information storage part; and an indication image superposing part for superposing a mounting position indication image indicating the mounting position of the sample container 4 which has been specified to the captured image.