Abstract: To address the problem of surface peeling defects in 022Cr18Ti ultra-pure ferritic stainless steel hot-rolled pickled strips, the causes of the defects were investigated and process optimization measures were proposed. The 3.5 mm×1 245 mm steel strips with peeling defects were used as test materials. The macroscopic morphology, microstructure and composition characteristics of the defects were systematically analyzed by optical microscopy, stereomicroscopy, field emission scanning electron microscopy and energy dispersive spectrometry. The results show that the surface peeling defects of the steel strips are divided into linear and spindle-shaped types. The linear peeling defects are mainly distributed in the 1/4 or 3/4 width area of the steel strip, and the spindle-shaped peeling defects are characterized by severe damage at both ends and slight concave pits in the middle. The core cause of the linear peeling defects is slag entrainment in the continuous casting mold, and the abnormal H₂S content in the coke oven gas in the heating furnace causes sulfur segregation and high-temperature corrosion, which further aggravates the defect development. The spindle-shaped peeling defects are jointly induced by insufficiently modified Al₂O₃ inclusions and TiN and its composite inclusions precipitated during the casting process. Both types of inclusions cause microcracks in the matrix during rolling and expand continuously, eventually leading to the stripping of the surface metal. In response to the causes of the defects, targeted process optimization schemes were proposed for the refining, continuous casting and heating processes, controlling w(Ca)/w(Al)≥0.15 in the LF furnace and w(N)≤0.010% in molten steel, optimizing the structure of the continuous casting nozzle and using special mold powder, and controlling the H₂S mass concentration in the coke oven gas below 30 mg/m³. After process optimization, the occurrence rate of peeling defects in 022Cr18Ti hot-rolled pickled steel strips decreases from 0.67% to 0.29%, which effectively improves the surface quality of the product and production efficiency, and provides a technical reference for the prevention and control of similar defects in ultra-pure ferritic stainless steel.