High-pressure ratios in transonic compressor rotors and fan blades pose challenges such as supersonic speeds and shock waves, which can result in boundary layer separation and potential performance issues. This study presents experimental research exploring the effect of surface roughness on shockwave-boundary layer interaction (SBLI). By employing various measurement techniques, the study provides a comprehensive overview of how surface roughness affects SBLI, enriching the dataset for internal flows across four specimens with different roughness parameters. The findings indicate that lower roughness surfaces lead to larger separation bubbles and more typical shock structures, whereas increased roughness results in smaller separation bubbles but higher flow instability.