By analyzing the technology process of all steel radial truck tire building machine, the author finds that there is a big potential of improvement both in stitching effect and efficiency. A new kind of stitching and control device is designed to replace the original. The new device can realize the soft stitching of tire, which reduces redundant actions and thus optimizes the process and improves the stitching efficiency. It is found in tests that the optimized process reduces the blister defectives greatly. Both productivity and quality of tires are improved significantly. It shows a big economic benefit.