The effect of polyhydroxyphenols on the new chemiluminescence (CL) system of isothiocyanatoisoluminol (ITCI) was studied. Pyrogallol was found to enhance the CL obviously, which provided a new CL method for the determination of pyrogallol. Effect of pH, KIO4 and ITCI concentration on the CL intensity of the system was investigated. An intensive interference study of usual ions and screen reagent was also carried out. Under optimum conditions, a linear relationship between pyrogallol and CL intensity was observed in the range of 1.75 x 10(-8) -2.5 x 10(-6) mol x L(-1). The detection limit of pyrogallol was 3.49 x 10(-9) mol x L(-1) (DL = 3 s/r). The relative standard deviation was 5.60% (5 x 10(-7) mol x L(-1) pyrogallol, n = 9). Furthermore, the method has been applied to the detection of pyrogallol in a simulated sample with satisfactory results. The recovery of the method was 94.0%-112.0%.