<p dir="ltr">The Fused Filament Fabrication (FFF) technique of additive manufacturing has enabled the use of bio-based polymers like Polylactic Acid (PLA), therefore promoting sustainability in the AM industry using eco-friendly filament instead of synthetic plastics that have long dominated the AM industry. However, PLA’s brittleness limits its broader applicability, leading to the exploration of natural fiber fillers, such as flax, hemp, jute, kenaf, and ramie, to enhance the mechanical, thermal, and aesthetic properties of PLA-based AM filaments. This study investigates the use of untreated hemp straw as a filler to improve the elongation at break of PLA, with a particular focus on the environmental implications of using hemp compared to pure PLA. Tensile specimens from both hemp-based and pure PLA materials were fabricated and assessed. A gate-to-grave life cycle assessment (LCA) was performed using SimaPro and the <i>Ecoinvent</i> database, employing ReCiPe 2016, CED, and IPCC 2021 GWP100 methodologies. Findings revealed that hemp-based specimens exhibited a significantly lower environmental impact than pure PLA, attributed primarily to the reduced energy consumption and emissions during the production and processing of hemp-PLA, as well as the resulting lower composite density using hemp straw. A sensitivity analysis of transportation distances and impact assessment methods (IMPACT World+ and TRACI) showed consistency in the overall environmental evaluation, with minor variations in certain impact categories. This study underscores the potential of hemp-PLA as a more sustainable material for additive manufacturing, especially in applications where ductility is a priority. Future research should explore the environmental impacts of using treated hemp-based straw, hurd, and fiber fillers as they offer possibilities for enhancing the properties of PLA.</p>