This dataset contains supplementary data for the journal paper: 'Prediction of the peak and steady-state ply-ply friction response for UD C/PAEK tapes' published in Composites Part A: Applied Science and Manufacturing. The dataset includes experimental ply-ply friction data measured on UD C/PEEK and C/LM-PAEK tape in melt using a friction tester located at the University of Twente, simulating the response during actual hot press forming of thermoplastic matrix composites. A range of sliding rates was measured to investigate the underlying mechanism for the typical friction response observed in start-up ply-ply friction tests. The experimental procedure is outlined and an overview of the used specimens with the test conditions is provided. Data on microscopy is included, which was used to determine the matrix interlayer thickness distribution in the ply-ply interface. Subsequently, this matrix interlayer thickness distribution was used to predict the peak and steady-state shear stress using a shear flow model as proposed in the mentioned paper. The dataset includes the scripts for the shear flow model as well as the required matrix viscosity data. The Matlab scripts are named according to the figures as shown in the mentioned paper.