The influence of substrate type on larval chironomid community structure was studied in a controlled experiment utilizing small artificial ponds. Wading pools containing three types of sterilized sediments of different particle size and organic content were colonized naturally over two eight-week periods. Total abundance and species composition varied with substrate type. Clay treatment ponds had the lowest abundance and were dominated byChironomusspp. Gravel and sand-silt treatment ponds were dominated byKiefferulus dux.Results agree with field studies and indicate that substrate is important in structuring chironomid assemblages in lakes and ponds. Data obtained using multiplate samplers did not agree well with data from benthic samples, indicating that artificial substrates do not always provide a representative sample of the benthic habitat.