Soft realtime scheduling of the hardware tasks is one of the key factors which affect the performance of dynamic reconfigurable systems. This paper presents a scheduling algorithm MSSA (minimun space scheduling algorithm) based on the minimum space between the hardware tasks of the vertex list. The algorithm constitutes a threedimensional resources model according to the length,width and the activation time to reach the adjacent degree of the task and the task placed in the threedimensional space to construct the cost function, which obtains the place position and the start time of the greatest value of the cost function and enables the task scheduling even more compact, reducing the waste of the system resources to improve the degree of parallelism.The simulation results show that this algorithm has a higher chip utilization and acceptance rate of tasks compared with the MSG4V algorithm and the Stuffing algorithm.