the front row of the left rack from position p 2 are respectively transferred as illustrated in fig1 a and 15d as described above after the sample tube is transferred the space on the right side of the right rack and the space on the left side of the left rack are no longer used for transfer accordingly mechanism inside sample analyzer 1 can be provided therein so that miniaturization of sample analyzer 1 can be achieved however in this transfer path since the sample tube travels around the left side of the right rack as illustrated in fig1 b and the sample tube travels around the right side of the left rack as illustrated in fig1 c the transfer distance is longer than that in the embodiment for this reason to shorten the transfer time it is preferable that the space on the right side of the right rack and the space on the left side of the left rack be used for the conveyance path also in the embodiment the sample tubes taken out from the rear row of the right and left racks are transferred as illustrated in fig1 c and 12c and the sample tubes to be returned to the rear row of the right and left racks from position p 2 are transferred as illustrated in fig1 d and fig1 d however the embodiment is not limited to this the sample tubes taken out from the rear row of the right and left racks may be transferred passing space s 3 after being slightly forwardly transferred also the sample tubes to be returned from position p 2 to the rear row of the right and left racks may be returned to the original holding position after being transferred passing space s 3 however even.