For the application in dentistry, the friction and wear behaviour of the thermoplastic polymer polyether ether ketone (PEEK) was analysed. Therefore, the friction coefficient and specific wear rate of PEEK against human enamel/dentine was investigated under various wet conditions. The tooth specimens consisting of enamel and dentine were prepared from nine mandibular molars. The sliding friction as well as the material loss of the counterparts was determined by using a block-on-ring rotational test configuration with a boundary film lubrication (deionised water). The material loss was measured by profilometry. The results were statistically analysed by one-way analysis of variance (ANOVA). As a result, the counter surfaces of the tooth samples showed a higher hardness and were stiffer than the polymeric specimens made of PEEK. The initial sliding friction coefficient varied in the range of μ = 0.23-0.44 for the three investigated rotational velocities from 1 m/s to 0.1 m/s and the stationary values were measured in the range of μ = 0.54-0.58 for the total sliding path of 1500 m. The resulting specific wear rate of PEEK was significantly higher w_s = 80 ± 65.5 10^-6 mm³/Nm than the coefficient of enamel/dentine w_s = 0.9 ± 0.7 10^-6 mm³/Nm (p < 0.01). In most cases, a significant increase of averaged surface roughness of the tooth samples was determined after tribological tests. In general, the investigations obtained a low removal of dental hard tissue (enamel, dentine) compared to the material loss of PEEK.