Laevistrombus canarium is one of the marine gastropod mollusks that have high commercial value,particularly in the aquaculture sector in Malaysia.This study was conducted to determine the feeding and food items of L.canarium at dif ferent ontogenetic stages(juveniles,sub-adults and adults)from Merambong shoals,Malaysia.Field observations on feeding activity were conducted,followed by detailed laboratory analysis on the stomach content.Five-minutes observations on randomly selected individuals were conducted at the fi eld sampling site and their feeding activities were recorded with reference to age stage.Various shell sizes from each ontogenetic stage were randomly collected and quickly anaesthetized with ice and preserved in 10%formalin before being transported to the laboratory for stomach content analyses.Field observations showed that L.canarium mainly grazed on epiphytes occurring on seagrass(46.67%),followed by sediment surface(40%)and epiphytes occurring on macroalgae(13.33%).Stomach content analyses showed a signifi cant dif ference(P<0.05)in gastro-somatic index(Gasi)between the juveniles(0.39±0.05),sub-adults(0.68±0.09)and adults(0.70±0.05)(P<0.05).Food items found in the conch stomach include diatoms,detritus,foraminifera,seagrass and macroalgae fragments,sand particles and shell fragments.The Index of Relative Importance(%IRI)indicates three main types of food dominated the three ontogenetic stages namely diatoms,sand particles and detritus.However,no signifi cant diff erence(P>0.05)was detected between the three main food items(diatoms,sand particles and detritus)among the ontogenetic stages.Therefore,feeding activity revealed the role of the dog conch in the marine food network.While,classifi cation of the types of food consumed by L.canarium through stomach content analysis determines the particular position of the gastropod in the food chain.Further studies are needed to provide a better insight between trophic relationships of L.canarium with marine ecosystem. Laevistrombus canarium is one of the marine gastropod mollusks that have high commercial value, particularly in the aquaculture sector in Malaysia. This study was conducted to determine the feeding and food items of L.canarium at dif ferent ontogenetic stages (juveniles, sub-adults and adults) from Merambong shoals, Malaysia. Field observations on feeding activity were conducted followed by detailed laboratory analysis on the stomach content. FIVE-minutes observations on randomly selected individuals were conducted at the fi eld sampling site and their feeding activities were recorded with reference to age stage. Variables shell sizes from each ontogenetic stage were randomly collected and quickly anaesthetized with ice and preserved in 10% formalin before being transported to the laboratory for stomach content analyzes. Field observations showed that L.canarium mainly grazed on epiphytes occurring on seagrass (46.67%) followed by sediment surface (40%) and epiphytes occurring on macroalgae (13.33%). St omach content analyzes showed a signifi cant dif ference (P <0.05) in gastro-somatic index (Gasi) between the juveniles (0.39 ± 0.05), sub-adults (0.68 ± 0.09) and adults Food items found in the conch stomach include diatoms, detritus, foraminifera, seagrass and macroalgae fragments, sand particles and shell fragments. The Index of Relative Importance (% IRI) indicates three main types of food dominated the three ontogenetic seeds are diatoms, sand particles and detritus. However, no signifi cant diff erence (P> 0.05) was detected between the three main food items (diatoms, sand particles and detritus) among the ontogenetic stages. Beforefore feeding activity revealed the role of the dog conch in the marine food network. Whilst classifying the types of food consumed by L.canarium through stomach content analysis determines the particular position of the gastropod in the food chain. Future studies are needed to provide a better insight between trophic relationships of L. canarium with mar ineecosystem.