Abstract: This study investigates the use of X-ray technique in estimating the gastric emptying time in whiting (Merlangius merlangus L.) fed in the laboratory conditions. All the experimental fish was fed to satiation with their natural prey sprats. The disperse type radio-opaque compound Barium Sulphate (BaSO4) paste was pre-injected in the body cavity of sprats in proportion to the body weight (0.1 to 0.15 ml/g sprat) prior to the experimental feeding. The BaSO4 paste was found suitable to portray the actual movement of food/prey items over different time since feeding that for fish that took larger satiation meal required longer time to empty the stomach. Results of this study disapproved the earlier claimed that the gastric emptying times (GET) remained constant as meal size increased. Results on modeling of satiation feeding were also discussed.