The numerical model for analysis of fire behavior of the spatial pre-stressed steel structure is established based on the software Marc. Analysis of thermal response and structural response of a suspended pre-stressed steel reticulated lattice shell are computed for the key nodes of the structure. For comparison, the air temperatures near the key nodes are also calculated based on the practical formula of large space air temperature rise. The different location of fire source is considered for analysis of response temperature, displacements and stresses of the nodes of the pre-stressed lattice shell. It is shown that the air temperatures obtained from the practical formula was always higher than the response temperatures of the nodes of the lattice shell during a quite long time after a fire takes place. The results show that the displacement of the node near the center of the gymnasium in fire is close to that of the node right above the inner cable, and the displacement of the node right above the outer cable is much less than the result of the center node.