Since high spatial resolution thermal infrared images can provide more details of target scenes, they are widely used in the fields of computer vision, medicine and remote sensing etc. Because it is usually more expensive to improve the performance of a thermal infrared camera, the super-resolution reconstruction algorithm is selected to improve the spatial resolution of thermal infrared images. The thermal infrared images to be reconstructed are obtained in the flight test over Zhoushan. The thermal infrared camera used is designed and equipped independently. The thermal infrared images are reconstructed by using the iterative back-projecting algorithm and the Projection onto Convex Sets Approach algorithm respectively. The experimental results show that both algorithms can improve the spatial resolution of thermal infrared images effectively.