The present investigation was carried out to study the chalidid species diversity in Horticultural ecosystem at Horticultural Research Station, Thadiyankudisai, Dindigul, Tamil Nadu from January, 2018 to January, 2019. A total of 257 numbers of individuals were recorded under 4 families, 9 genera and 10 species. The seasonal abundance studies revealed that the highest population of species was recorded in South West Monsoon (SWM) (52.9%) followed by winter season (32.7%) and the least number of species during North East Monsoon (NEM) (5.8%). The species diversity comprised of Copidosoma floridamum (24.5%) followed by Dipara sp. (13.2%), Brachymeria jambolana (10.9%), Agarwalencyrtus citri (10.5%), Gonatocerus sp. (10.1%) and (Lymaenon delhiensis and Epitranus sp.) (7.8%). The least... population was recorded in Haltichella sp (3.5%). Insect pests are a major constraint in achieving higher yields in Horticulture, hence, the studies of Chalcidoidea diversity is crucial for success in biological control.