To realize efficient use of waste ink tanks by solving the conventional problem that idle jetting to a plurality of waste ink tanks is carried out according to preliminarily uniformly determined procedures irrespective of a difference of volumes of waste ink tanks, thereby resulting in a situation in which waste ink of an amount matching the volume of each waste ink tank cannot be accommodated in an ink jet recorder.

The ink jet recorder has a recording head 14 with ink jet nozzles, a carriage 13 which moves a printing region and outside the printing region while loading the head, reliability maintaining recovery mechanisms 37 set at a plurality of idle jetting positions 110 and 114 outside the printing region, respectively, and a control part for idly jetting the waste ink from nozzles when the recording head is located at each idle jetting position. The reliability maintaining recovery mechanism is equipped with a plurality of waste ink tanks 113 and 115 which hold waste ink absorbers 111 and 116 for absorbing idly jetted ink drops. The control part selectively moves the carriage to each idle jetting position to idly jet the ink so that the number of idle jetting times to each waste ink tank at each idle jetting position is proportional to a volume ratio of each waste ink tank.