The aim of the present study is to know the occurrence and distribution of molluscan wood-borers from Chilika lagoon in relation to some physico-chemical parameters .The samples were collected from three stations during May 2010 to April 2011. Six wood-borers belonging to Family Pholadidae and Teredinidae namely Martesia striata and five borers, namely, Bankia brevis (Deshayes), Bankia campanellata (Moll and Roch), Bankia sps., Lyrodus pedicellatus (Quatrefages) and Teredo furcifera were observed. The physicochemical parameters like air temperature , surface water temperature , pH, salinity, and dissolved oxygen were studied from these stations. The air temperature varied 28.5 to 35.4ºC. The surface water temperature was lowest being 27.5ºC in post-monsoon at station-3 and the highest surface water temperature was 32.8ºC during pre-monsoon at station -1. The highest and lowest pH was observed to be 8.9 during monsoon in station- 1 and 7.5 during post-monsoon in station -1. Similarly the highest and lowest value of salinity was observed to be 19.5% at station - 3 during pre-monsoon and 14.26% at station-2 during monsoon. Likewise the highest and lowest dissolved oxygen were observed to be 11.5 mL/L during pre-monsoon at station -1 and monsoon at station-2.