A certain component features an overall thin-walled structure with a wall thickness less than 1 mm, manufactured from high-strength martensitic precipitation-hardening steel. This part demands extremely stringent dimensional accuracy, with circumferential wall thickness variation not exceeding 0.006 mm, making it a typical high- precision thin-walled component. To ensure component performance and material utilization, the primary forming processes include spin forming, solution heat treatment, and multiple turning operations. During actual machining, martensitic precipitation-hardening steel exhibits significant microstructural stress relaxation and uneven cooling after solution heat treatment, leading to substantial part deformation. This makes it difficult to control subsequent machining dimensions within tolerance limits. Additionally, conventional clamping methods during multi-pass turning operations often cause uneven stress distribution on components during processing, frequently resulting in dimensional deviations that severely impact finished product yield rates. To address this challenge, this study systematically developed specialized tooling design and optimized turning processes tailored to the structural characteristics and deformation mechanisms of these thin-walled tube blanks. Simultaneously, a gap-free turning fixture with uniform expansion and clamping capabilities was developed. Combined with optimized machining parameters during the turning stage, this significantly improved stress distribution during processing, preventing further deformation caused by localized stress concentration. Test results indicate that after process optimization, the overall machining accuracy of this component improved by approximately 70% compared to the original process. Critical geometric tolerances showed significant enhancement, with roundness error consistently controlled within 0.30 mm and diameter dimensional consistency markedly improved. These measures not only successfully addressed deformation control challenges during heat treatment and machining of thin-walled parts but also provided a viable process solution and technical reference for precision manufacturing of similar high- difficulty, high-precision components.