The main island of Pingtan Comprehensive Pilot Zone, Haitan Island, which is the zone nearest to Taiwan Province, is the fifth largest island in China and the largest island in Fujian Province. With the development and increase in the urbanization of Pingtan, the beach tourism industry has developed rapidly. However, the beach is a simple and sensitive ecosystem, and the development of beach tourism would affect the assemblages and distribution of benthos, which would affect the structure and function of the sandy beach ecosystem. It is necessary to study the biological baseline and establish basic data for the evaluation of the ecosystem in Haitan Island. Meiofauna is one of the most important indicators of marine environmental quality owing to its ecological characteristics, such as high abundance and short life cycle. In order to study the groups, abundance, and distribution of meiofauna, feeding types and species diversity, age structure and sex ratio of marine nematodes, meiofaunal samples were collected from the sandy beach of Changjiangao, Haitan Island in Fujian Province in 2013 and 2014. The results showed that the mean annual abundance of meiofauna was (810.87±696.75) ind/10 cm², consisting of 16 meiofaunal assemblages. Nematoda was the most dominant group, accounting for 52.36%, followed by Gastrotricha, which constituted 21.14%. The mean annual abundance of nematodes was (424.54±400.23) ind/10 cm², the abundance varied seasonally as follows:summer ((783.45±336.45) ind/10 cm²) > spring ((600.67±309.42) ind/10 cm²) > autumn ((298.26±424.57) ind/10 cm²) > winter ((113.05±95.79) ind/10 cm²). A total of 105 species of nematodes were identified in the four seasons, belonging to 75 genera and 26 families. There were 10 genera of nematodes with dominance greater than 5% in the four seasons-Axonolaimus, Theristus, Metachromadora, Mesacanthion, Rhynchonema, Epacanthion, Microlaimus, Viscosia, Lauratonema, and Enoploides, but the dominant genera varied seasonally. Hierarchical cluster analysis showed that the nematode communities in spring, summer, and autumn shared greater similarity than those in winter. The percentage of the mean annual abundance of feeding types were 1B (32.19%) > 2A (31.32%) > 2B (31.12%) > 1A (5.37%), among which 2A and 1B were dominant in spring and summer, whereas 2B and 1B were dominant in autumn and winter. The number of nematode genera in autumn was the largest, whereas that in winter was the lowest. Nematode diversity was the highest in autumn (d=8.45, H'=3.36) and the lowest in winter (d=7.36,H'=2.92), and the diversity in spring and in summer was similar. The age structure of the nematodes revealed that the proportion of juveniles accounted by 45.47%, and the sex ratio (femalemale) was 1.10:1.