Meiofauna are referred to metazoans, including some protozoans, that can pass through sieves between mesh size of 1 mm (or 0.5 mm) and 0.042 mm (or 0.031 mm). Meiofauna are one of the most important components of the benthic ecosystem and serve as a key link in the benthic food web. They are ubiquitous in nature, with short generation time, small body size and high metabolic rates. Thus their metabolic activity has a direct effect on the rate of matter and nutrient recycling within the benthic ecosystem. Although there are many studies on meiofauna in Chinese seas, such as the Bohai Sea, Yellow Sea and East China Sea, there are only a few reports about meiofauna related to the southern Yellow Sea Cold Water Mass. In this paper, metazoan meiofaunal assemblage, abundance, biomass and spatial distribution in relation to benthic environmental variables at 23 stations in the southern Yellow Sea Cold Water Mass and its adjacent waters in summer 2011 were investigated. The results showed that a total of 20 taxa of meiofauna were identified. The average abundance and biomass of meiofauna were (1194±873) ind./10 cm² and (881±669) μg dwt./10 cm², respectively. Free-living marine nematodes were the most dominant meiofaunal group, comprising 89.7% of total abundance and 49.0% of total biomass, followed by benthic copepods (5.5%), crustacean nauplii (1.8%) and polychaetes (1.2%) in terms of abundance, and polychaetes (22.9%), benthic copepods (13.9%), ostracods (7.8%) and tubellarians (2.0%) in terms of biomass. For vertical distribution, 79.1% meiofauna were found in the surface 0-2 cm depth of the sediment, 16.4% in 2-5 cm depth and 4.5% in 5-8 cm depth. The abundance and biomass of total meiofauna showed significant positive correlation with chlorophyll a concentration, while the biomass of the total meiofauna showed significant negative correlation with the concentrations of heavy metals Pb, Cu, Fe, Ni and Co in the sediment and a significant positive correlation with Cd. BIOENV analysis showed that the combination of moisture content, organic matter content and grain size of sediment can best explain the difference of meiofaunal assemblages among the stations. Based on the abundance and biomass of meiofauna, the study area can be divided into three regions, including the centre of cold water mass, area at the perimeter of the cold water mass and the coastal waters. Among the three regions, the abundance and biomass at the perimeter of the cold water mass were the highest, followed by that in the central area of the cold water mass and the coastal water area. The average abundance and biomass of meiofauna in the cold water mass area was 2.3 and 2.1 times of the coastal waters, respectively.