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Description: The sense of body ownership refers to the feeling that one's body belongs to oneself. Researchers use bodily illusions such as the rubber hand illusion (RHI) to study body ownership. The RHI induces the sensation of a rubber hand being one’s own when the fake hand, in view, is stroked simultaneously with one's real hand, which is hidden. The illusion occurs due to the integration of vision, touch, and proprioception, and it follows temporal and spatial congruence rules that align with the principles of multisensory perception. For instance, the rubber hand should be stroked synchronously with the real hand and be located sufficiently close to it and in a similar orientation for the illusion to arise. However, according to multisensory integration theory, the congruence of the tactile prosperities of the objects touching the rubber hand and real hand should also influence the illusion; texture incongruencies between these materials could lead to a weakened RHI. Nonetheless, previous studies on texture incongruence have produced contradictory results. In this study, we employed a more stringent perceptual discrimination paradigm to investigate whether texture incongruencies modulate the RHI. Using signal detection theory analysis, we discovered that texture incongruencies influence the RHI through perceptual bias leading to stronger illusion reports for the rubber hand touched by the same material as their real hand; texture incongruence does not influence sensitivity to visuotactile asynchrony. Moreover, there was an interaction between bias and asynchrony, so that the body ownership bias for congruent textures were the greatest for shorter synchronies (50-100 ms) and disappeared for longer asynchronies (200 ms), in line with perceptual bias being most pronounced under conditions with weaker sensory information. We suggest that the body ownership bias towards congruent textures is perceptual and reflect top-down processes related to previous visual and tactile experiences from interacting with objects with different material properties.