Alpaca fibre exhibits different quality grades based on fibre diameter and is regulated by the Peruvian Technical Standard – NTP 231.301.2022; however, there are few studies on its cross-sectional characteristics and tensile strength as a function of these different qualities. This study aimed to investigate the cross-sectional characteristics, fibre diameter, and tensile strength in relation to the quality grades. Seven fibre quality groups were established by measuring fibre bundles, and four samples were taken from each group. The cross-sectional characteristics, fibre diameter, and tensile strength were measured using the Fiber Mult, Fiber EC, and Fiber TST devices, respectively. All three variables were affected by fibre quality (p<0.05), showing larger cross-sectional areas and diameters in lower-quality fibres, while tensile strength increased up to quality grade 5 (Fine) bef...