To address the task scheduling problem of industrial software using Service-Oriented Architecture （SOA）， a task scheduling algorithm for SOA-based industrial software was proposed， considering the multiple attributes of tasks， the randomness， time-varying and coupling relationships of attributes， and the requirements of real-time scheduling and parallel processing of tasks. Firstly， the task scheduling problem was modeled， and a utility function was designed to evaluate the importance of the task. Then， Importance Ranking-based Scheduling Algorithm （IRSA） was proposed to schedule tasks in descending order of importance. Finally， a resource reservation mechanism and a preemptive scheduling mechanism were designed in IRSA to improve the efficiency of task scheduling. Experimental results show that compared with the four online scheduling algorithms such as First Come First Serve（FCFS）， Earliest Deadline First（EDF）， Least Laxity First（LLF）， and Fixed Priority Scheduling（FPS）， when the number of arrival tasks per second reaches 7.99， IRSA reduces the average response time of tasks by 55.83% to 61.27%， respectively， and has significant advantages on all performance metrics. Therefore， IRSA can achieve efficient task scheduling for SOA-based industrial software.