Due to the anisotropy of the x-cut thin-film lithium niobate optical integration platform, the transverse magnetic (TM) mode of the optical waveguide is prone to mode hybridization and coupling to other modes during bending, posing a challenge to the bending of the TM mode. This article takes a 400 nm thick, semi-etched lithium niobate waveguide as an example to analyze the mode hybridization phenomenon of TM₀ mode under different waveguide widths and transmission directions, and simulates its 90° bending transmission performance. The findings indicate that within a certain waveguide width range (approximately 1.7 μm to 2.15 μm), no mode hybridization occurs when bending the TM₀ mode. However, for waveguide width lower than 1.7 μm or higher than 2.15 μm, coupling between the TM₀ and TE₁ (or TE₂) mode occurs. Experimental demonstrations further corroborate this conclusion. This study offers a design methodology for achieving TM mode bending in thin-film lithium niobate waveguides, with potential applications in polarization-control-related optical integrated devices on this platform.