A fuzzy sliding mode control strategy for container cranes is discussed in this paper. In which, the sway motion of a payload is integrated into the trolley dynamics in a sliding surface. This scheme guarantees the asymptotic stability of the closed-loop system. Moreover, the control gain, which is the most important component, is a flexible gain and is tuned based on fuzzy laws to avoid chattering phenomena of the system. The performance of the closed-loop system has been simulated using MATLAB. In addition, to illustrate the efficiency of the proposed control law, experimental results are also provided.