Abstract: To aim at the property that task scheduling in cloud computing environment is NP hard and according to the swarm intelligence theory,a kind of task scheduling algorithm optimized by bat algorithm is proposed.Firstly the model of task scheduling in cloud computing and the rule of subtask's number is is given.Then bat position coding program in continuous space is proposed,and fitness function is defined.Lastly subtask scheduling in cloud computing optimized by bat algorithm is implemented. The emulation result proves that task scheduling algrothrim optimized by bat algorithm given in this paper can decrease task's completion time obviously compared to other scheduling algrothrim and increase resource operating factor.