By increasing the intensity in marine organisms farming, there is a need for monitoring the impact of fish farm on the environment. One of the main impact of intensive fish production is variability in qualitative and quantitative composition of meiofaunal and macrofaunal community structure. The objective of this study was to determine the impact of sea bass and sea bream farms on the marine environment through changes in the meiofaunal abundance and community structure in the sediment. Sediment samples were collected in three replicate corers by SCUBA diving at three stations: at the edge of the cages (i.e., ST 1) directly below the farm cages (i.e., ST 2) and at the control station (i.e., CTRL ST) situated at distance of approximately700mfromthefishfarm. Physical-chemical parameters such as temperature, salinity, saturated oxygen, dissolved oxygen, chlorophyll-a, turbidityand pHvalues of water columnwere also recorded during the sampling. After collecting and storing the samples, organisms were separated from the sediment, counted and identified on microscope under magnification from 40× to 400× depending on the species. These results showed a significantly higher number of meiofaunal taxa on the control station comparing to the stations at the edge of the cages, and directly below the cages, which confirms the impact of fish farm. The greatest differences in total abundance of meiofauna were found in the sediment surface layer (i.e., 0-1 cm) between the control station and P1, while total abundance of meiofauna was the highest in P2, caused by deposition of organic matter in the sediment below the fish farm. All stations are dominated by Nematoda and Copepoda, while rare taxa (e.g., Bivalvia, Ostracoda, Tardigrada, Larve Priapulidi)were recorded onlyat thecontrol station.Furthermore, significantlyhighernumber of rare meiofaunal taxa was found at control station than at stations P1 and P2. These results indicate at changes and higher variability in terms of meiofaunal abundance and community structure caused by deposition of organic matter in the sediment below the fish farm, pointing out the importance of regular monitoring and use of meiofauna as an additional indicator for environmentalmonitoringandchangesintheenvironmentcausedbycontamination.