Plant fibres and the artefacts constructed from them often remain overlooked in the archaeological record because of their poor survival and the problems related to the precise identification of the species to which the fibres belong. The goal of this study was to design a simple and accurate method of identifying archaeological plant fibre sources. Twenty-two fibre samples from two sets of ancient Egyptian botanical artefacts were examined under both a stereomicroscope and a compound microscope, and compared to a large reference collection and to previously published research. By examining longitudinal thin sections of the ancient plant specimens, we identified plant fibres from the following species: Hyphaene thebeica, Cyperus papyrus, Desmostachya bipinnata, Imperata cylindrica, Phragmites australis and Linum usitatissimum. Our identification of these plant fibres reveals essential information about the materials used for producing ropes, baskets, sandals, mats and fabric. The results of this study demonstrate the value of longitudinal thin sectioning and light microscopy as a major means of identifying the source material of botanical artefacts, and advance our knowledge of ancient Egyptian plant exploitation as well as the associated technologies involved in constructing these types of artefacts.