Based on data from the macrozoobenthos resource survey along Yanpu Bay in October 2014 (autumn) and October 2016 (autumn), variation in the ecological niche and functional groups following planting of were studied via niche breadth, niche overlap, functional group classification, and redundancy analysis (RDA). The results showed that the proportions of the wild niche and middle niche species increased after planting whereas that of the narrow niche species decreased. The species pair comprising (0.94) presented the highest niche overlap before planting, whereas those of Assiminea violacea and (0.99) were highest after planting. Compared with the diversity index of the functional groups before planting, the diversity index of the functional groups in high and middle tidal zones was increased whereas that in low tidal zones was reduced after planting. Densities of the planktophagous group (Pl), phytophagous group (Ph), and omnivorous group (Om) increased whereas that of the carnivorous group (Ca) decreased slightly compared with the year before planting. There were significant differences (<0.05) between the high and low tide zones, as well as the middle and low tide zones after planting; however, the relationships between each pair of intertidal zones were not significantly different (>0.05) before planting. The RDA concluded that the factors with greater effects in macrozoobenthos communities changed from lead, cadmium, and petroleum before planting to zinc, cadmium, and arsenic after planting. In summary, planting along Yanpu Bay had a positive effect on the overall improvement of the ecological niche and functional groups of macrozoobenthos.