Abstract: A novel, simple flow injection chemiluminescence method was presented for the determination of phloroglucinol. In the system of luminol-KIO_4 phloroglucinol, a trace amount of phloroglucinol can enhance the chemiluminescence intensity. The linear range for the detection of phloroglucinol is 2.0×10~(-7)~1.0×10~(-5) mol/L, the detection limit is 7.8×10~(-8) mol/L. This method has been used for the determination of phloroglucinol in river water with satisfactory results.