The increasing impact of human activities,global warming,rising sea levels and alien species invasion are major drivers of ecological changes in the benthic ecosystems of the Pearl River Estuary. Despite of the large number of estuary investigation projects carried out in the Pearl River Estuary,evidence for longterm dynamic diversity of macrobenthos is scarce. To improve the understanding of the evolution and degradation mechanism of diversity,11 standardized field studies were carried out in the Pearl River Estuary in 2015. Based on macrobenthos data collected in 2015 in the Pearl River Estuary,biological parameters such as diversity,richness,biomass and abundance were calculated. A total of 67 macrobenthic species were collected from six cruises. The main taxonomic groups identified were polychaeta (27 taxa),crustacea (24 taxa),mollusca (12) and other groups (4) . The values of abundance and biomass varied from 8 to 1 192 ind ·m~(-2) and from 0. 02 to 42. 50 g·m~(-2),respectively. The highest abundance values were recorded in Yamen in June(1 192 ind·m~(-2)) and September(1 048 ind·m~(-2)),and Hutaomen in September(1 048 ind·m~(-2)) . The highest biomass values were recorded in Yamen in September,Jitimen in May,and Modaomen in February-March,Jiaomen in April,with values all over 30. 00 g·m~(-2) . Grandidierella japonica,Paraphotis sinensis,Musculus senhousei and Moerella iribescens dominated the macrobenthic abundance. These species represented 70% of total macrofauna abundance in Yamen. Overall,these sites (Yamen,Jitimen and Modaomen) were represented by Sinonovacula constricta,Potamocorbula laevis and G. japonica for 70% of the total biomass. Dominant macrobenthos species revealed that the macrobenthos community structure of the Pearl River Estuary showed simple and individual miniaturization. The mean values of two indices ranged from 1. 11 to 1. 81 and from 0. 22 to 2. 02 for Shannon-Wiener index (H') and richness index (D) respectively. The ranges of H' diversity index values in eight sites indicated poor and deteriorative ecological status. The highest values of H' (2. 46) was recorded in Jitimen in March 2015. Abundance-biomass comparison (ABC) was applied to assess the estimated ecological quality in different months in the Pearl River Estuary. The study is to assess the environmental changes in different months by ABC curve and Shannon-Wiener (H') index in the studied areas. The ABC plots showed that the Pearl River Estuary could be classified as moderately disturbed and polluted in January. In frequent disturbance area,ABC must thus be used with singleness and combined with other indicators or indices,for an accurate and connected characterization.