Abstract: Scheduling task on a heterogeneous distributed grid environment is a challenging one and in general, has been shown to be a NP-complete problem. To solve the complicated scheduling problem, an efficient scheduling algorithm is essential. The major aim of the scheduling algorithm is in maximizing the resources utilization and in minimizing the makespan. This study addresses the complicated scheduling problem by proposing an efficient scheduling algorithm, Sort Completion Time Mean Tasks Scheduling algorithm (SCTMTS) which determines the order in which the tasks are to be scheduled to the appropriate resources. The first step is to sort the list of completion time of the task. The second step is to find the mean value of each task. Then the maximum mean value is obtained. Finally, the task that has the maximum mean value is selected and scheduled to the resource that has the minimum completion time. Experimental results reveal that the proposed sort completion time mean tasks scheduling algorithm out performs Min-min heuristic scheduling algorithm regarding both makespan and resource utilization.