Suppression of the swinging load is very important for increasing the operability of a floating crane in waves. In the first report, we proposed a effective method of suppressing a swinging load through controlling the floating body motion itself adding pnumatic actuator system. This was a very unique idea and the effectiveness of this method was confirmed through model experiments and numerical simulations, especially in long crested irregular waves. In the second report, we report about the results of this confirmation in more realistic experimental condition and by using more advanced controlling system also in directional spectrum waves. Namely, the swinging load is moved up and down direction in directional spectrum waves. This case, the natural frequency of swinging load is changed according time passed and transverse swing occurs. Furthermore, optimal control was introduced in numerical simulation.