<p>Carbon fiber-reinforced ceramic matrix composites have become key materials for aerospace hot-end components, thanks to their excellent properties including high strength, toughness and high-temperature resistance. The special arrangement of carbon fibers in the matrix endows these composites with anisotropic and heterogeneous characteristics. At present, a clear understanding of the material removal mechanism in ultrasonic elliptical vibration-assisted grinding remains lacking. This study investigates the ultrasonic elliptical vibration-assisted grinding removal mechanism under different structural orientations via single-grit scratching simulations and experiments, and analyzes anisotropy’s influence on surface morphology and scratching force. The results show that the fiber orientation angle plays a decisive role in surface morphology and subsurface damage, with interface failure dominating multimode failure behaviors. Variations in fiber orientation lead to a double-peak characteristic of scratching force, increasing with scratching depth. At <i>θ</i> = 0° and 5&#xa0;μm depth, tangential and normal scratching forces reach minimum values of 5.15&#xa0;N and 4.31&#xa0;N respectively. At 20&#xa0;μm depth, both forces exhibit peaks at <i>θ</i> = 30° and <i>θ</i> = 150°, corresponding to 20.01&#xa0;N (<i>θ</i> = 30°), 26.63&#xa0;N (<i>θ</i> = 150°) and 22.44&#xa0;N (<i>θ</i> = 30°), 23.10&#xa0;N (<i>θ</i> = 150°). The conclusions provide theoretical guidance for ultrasonic elliptical vibration-assisted grinding of ceramic matrix composite components.</p>