The behaviour of freely floating long structure due to the interaction of regular and random oblique waves is studied experimentally. The sway, heave and roll responses due to the action of long crested oblique waves evaluated using the two dimensional finite element technique (Sannasiraj et al., 1995) are compared with experimental investigations and the agreement is found good. The response amplitude operators (RAO) for the regular and random wave tests are compared well and, hence, the interaction between wave and long floating structure is linear. The effect of wave direction on the motion response is discussed in detail. The angle of wave approach is found to essentially reduce the response of the structure.