Abstract: Task scheduling is an important part of grid system, and the task scheduling algorithm is the most important in the task scheduling. After the research of MinMin algorithm, this paper points out the shortcomings of MinMin algorithm. With the goal of grid task scheduling, several improved MinMin algorithms are drawn out in optimal scheduling, load balancing, quality of service and the charge. Then this paper introduces the advantages and disadvantages of the improved algorithms. It provides some reference to improve the algorithms in the future. 

Key words: grid, task scheduling, MinMin algorithm