Acute toxicity test was carried out on the HgCl2 standard solution and the terrigenous sewage at the Pearl River estuary’s drainage outlets with Photobacterium leiognathi N1 strain separated from the luminescent fish and the Microtox acute toxicity testing system, respectively. The results showed that acute toxicity test results of the Photobacterium leiognathi N1 strain have good correlation with those of the Microtox toxicity test systems. The test results of the acute toxicity for the 9 monitoring stations of sewage for the terrigenous sewage at the Pearl River estuary were ranked in the order of the acute toxicity; of which, the ranking results of the 6 monitoring stations were identical. The comprehensive assessment of water quality was conducted on the chemical analysis of the water quality at the discharge outlets by means of the Nemerow index. The assessment results were then compared with the results of the luminescent bacteria acute toxicity test results. It showed that the assessment results of the Nemerow pollution index based on the physicochemical indexes had both the consistency and certain differences with the results of the acute toxicity test. The two results complemented each other in terms of the water quality status and pollution effect assessment. The research provided methodological basis for the pollution effect of the toxic pollutants and risk monitoring of the ecological damage at the sewage discharge outlets by means of the Photobacterium leiognathi N1 strain. The established method has relatively good consistency with the results of the Microtox toxicity testing system, and boasts the features of speed and low cost, thus exhibiting excellent application value.［Chinese Fishery Quality and Standards, 2014, 4(5):10-15］