<p>High-speed continuous casting represents a critical direction for optimizing current continuous casting technology, while addressing the various problems arising therefrom has become a central challenge for the next generation of technological innovation. Among these, the aggravated bulging deformation of strands under high casting speeds and the issue of molten steel deviation flow in the mold have emerged as particularly prominent, forming key bottlenecks that constrain the stability of the high-speed continuous casting process. In this study, an improved computational method for predicting bulging deformation under high-speed casting conditions is proposed, accounting for the effects of deviation flow. The proposed modeling approach and computational strategy were rigorously validated through comparisons with experimental data, previous studies, and empirical formulas, confirming their high reliability. Furthermore, this work analyzed the bulging deformation patterns at different strand locations, discussed the effects of deviation flow-induced non-uniform solidification and casting speed on slab bulging behavior, clarified the quantitative relationship between casting speed and the offset of the bulging peak, and revealed the formation mechanism of this offset phenomenon. This work provides a theoretical basis and technical support for optimizing bulging control in the continuous casting process.</p>