Five species of free-living marine nematodes are redescribed and illustrated as new records in the Yellow Sea of China. These species include one monhyterid, Campylaimus gerlachi in the family Diplopeltidae and four enoplids species, Oxystomina enlongata, Halalaimus lutarus and Halalaimus wodjanizkii in the family Oxystominidae. Ecological and taxonomical remarks are provided and discussed in comparison with original description. The key to all known species of the genus Campylaimus is given. Our fidings have oferred the taxonomic information of nematodes to benthic ecology and biodiversity studies of the Yellow Sea