The invention relates to a chemiluminescence measuring instrument and a measuring method of chemical liquid luminescence intensity. Current chemiluminescence measuring instruments have a large volume and a slow measuring speed. Therefore, the chemiluminescence measuring instrument comprises a micropore plate, a photoelectric sensor, and a micropore plate driving system; the micropore plate driving system can drive the micropore plate to move longitudinally; the chemiluminescence measuring instrument is characterized in that the instrument also comprises an optical fiber; one end of the the optical fiber is fixed on an input end of the photoelectric sensor, and the other end is a movable end, and is equipped with a transverse driving mechanism; the transverse driving mechanism can drive the movable end to move laterally above the micropore plate. For optimization, when the movable end of the optical fiber moves relative to the micropore plate, row-by-row reciprocating motion or column-by-column reciprocating motion is performed. The chemiluminescence measuring instrument of the invention has the advantages of small volume, high measuring speed, and high efficiency, and the measuring method of chemical liquid luminescence intensity of the invention measures during the reciprocating stroke, has a high speed, and high efficiency, and is applicable to the fields of biochemistry and clinical diagnosis.