A non-invasive sensing system has been developed for simultaneous measurement of chlorophyll and astaxanthin concentrations in H. pluvialis cells. A spectrofluorophotometric method was used to eliminate the disruption of the cells for extraction of the chlorophyll and astaxanthin in the cells as in conventional method. The emission signal at 368 and 411 nm was used for the detection of chlorophyll and astaxanthin in H. pluvialis cells respectively. The linear range in evaluation was between 0.50 and 20.0 ìg•mL-1 for chlorophyll and 1.00 and 12.0 ìg•mL-1 for astaxanthin. The limits of detection for the analytical procedure were found to be 0.35 ìg•mL-1 for chlorophyll and 0.25 ìg•mL-1 for astaxanthin. The relative standard deviations for the determination of 7.0 ìg•mL-1 chlorophyll and 5.0 ìg•mL-1 astaxanthin were 1.2 and 1.1%, respectively. The procedure was found to be simple, rapid, and reliable. This method was successfully applied to the determination of chlorophyll and astaxanthin concentrations in H. pluvialis cells. Good agreement was achieved between the results obtained by the proposed method and the HPLC method.