Abstract: This study focuses on the excitation of high-order linearly polarized (LP) modes in optical fibers and their applications in optical trapping, aiming to enhance the manipulation capabilities of single-fiber optical tweezers. Traditional optical tweezers have complex systems and high costs, while fiber optical tweezers, characterized by simple structure and high portability, serve as effective alternatives in complex scenarios. With advancing applications, high-order LP modes have been introduced into single-fiber optical tweezers. However, current excitation methods have certain limitations. Therefore, spatial light modulator (SLM) excitation technology was employed. Theoretically, optical field, phase, and polarization distributions of LP modes in fibers were analyzed. Under weak-guidance approximation, transverse components were perpendicular to each other and proportional, longitudinal components were negligible, and distinct phase differences existed among LP modes. Beam phase modulation using the SLM enabled excitation of the corresponding modes. Experimentally, an SLM-based optical system was constructed using optical fibers with specific parameters. The LP01, LP11, and LP21 modes were successfully excited, achieving average coupling efficiencies of 94%, 41%, and 30%, respectively. The excited modes demonstrated high stability and purity, showing minimal sensitivity to slight fiber disturbances. For optical trapping applications, experiments were conducted using a tapered fiber probe with a 50° cone angle under 8-mW output optical power. The results showed that the LP11 and LP21 modes effectively captured and manipulated 2-μm silica particles. LP21 mode exhibited the highest axial trapping efficiency of 3.6 pN/W among the three modes, while LP01 mode failed to achieve trapping. This study demonstrates that SLM excitation technology enables flexible and dynamic generation of high-order LP modes. Integrating these modes into single-fiber optical tweezers provides enhanced trapping functions, offering new solutions and potential applications for micromanipulation in biomedical fields.