This paper refers to the laboratory testing carried out on model caissons embedded in marine clay and the results of ultimate lateral loads. Ground level deflection of a caisson was measured for various embedment depth ratios (L/D) of caisson, load eccentricity ratio (e/D), and various undrained strength (su ) of clay. At a given lateral load, the deflection levels are increased as the e/D increases and decreased as L/D, su , and D increases. The ground level deflection (y) and the lateral load (P) data obtained in the testing have been expressed in the rectangular hyperbolic formulation. The agreement ratio obtained by comparing the actual ultimate lateral loads with the ultimate lateral loads of transformed hyperbolic representation showed narrow variation, hardly 2–14% and the average agreement ratio is 8%. The estimated lateral loads are observed to be slightly greater than the test values. Also the test data of lateral load-ground level deflection has been further analyzed using nondimensional plots to arrive at lateral capacity of caissons. The published results of previous researchers based on the tests conducted on field prototype models were compared with the trend of the test data and these are found to be quite satisfactory.