Abstract: Sample collection of sediment meiofauna was conducted in winter 2018.Five sampling sections were set along the southern distribution area of Techeng Island mangrove,and to study the composition and abundance of meiofauna in this mangrove wetland,as well as the community structure of marine nematodes.The results showed that five groups of meiofauna were found in the sampling area,among which marine nematodes were absolutely dominant group,accounting for 97.99% of the total abundance.The abundance of meiofauna was between(71.35±16.80)~(786.40±908.18)ind/10 cm²,while the average abundance of meiofauna was(432.25±500.84)ind/10 cm².In different sections,there was a significant difference in the number of meiofauna groups among different sections and tidal levels.The marine nematodes were identified as belonging to 44 genera of 22 families.Terschellingia, Sabatieria, Viscosia, Spirinia, Megadesmolaimus and Spilophorella were the dominant genera with the number of greater than 5%,with the dominant degrees of 21.77%,8.43%,7.99%,7.99%,6.50% and 5.79%,respectively.In terms of the number of genera and individuals,the deposit feeders were dominant.Through diversity and K-dominance analysis,the marine nematode index in section 3 was the highest.Cluster analysis and MDS analysis showed that section 3 and section 5 were similar in community structure of marine nematodes.