Background: PEEK material has been widely used recently. It serves multiple advantages being biocompatible, light material and has modulous of elasticity close to bone. It is used for fabrication of fixed partial dentures, implants abutment and superstructure. However, its surface roughness and bacterial adhesion needs further investigations. Aim: Evaluate surface roughness and bacterial adhesion of zirconia and PEEK. Materials and methods: A total of ten samples were obtained from PEEK and Zirconia where 5 samples were obtained from each material and sliced into discs. Polishing of the samples was done followed by surface roughness measurement for each disc. This was followed by incubating the samples in bacterial suspension to prepare them for bacterial adhesion testing. Results: Results showed that PEEK (0.52±0.06) had a significantly higher mean value than Zirconia (0.23±0.04) (p<0.001). Regarding bacterial adhesion test, PEEK showed higher adhesion values with 19.00±1.41, 6.20±1.30 and 5.66±0.44 for Streptococcus sangius, Streptococcus mutans and Candida albicans respectively whereas zirconia had bacterial adhesion values of 7.60±3.58, 3.60±0.55 and 2.80±0.84 for Streptococcus sangius, Streptococcus mutans and Candida albicans respectively. Conclusion: Within the limitations of this study, we concluded that Zirconia could provide smoother surfaces than that of PEEK. Moreover, bacterial adhesion on surfaces of PEEK exceeded that of Zirconia.