Hemp concrete is the most commonly used bio-based material for construction because of its hygrothermal behaviour and its contribution to reduce the environmental impacts and energy needs of buildings. Apart from these performances and environmental qualities, there is still a lack of information concerning hemp concrete durability and the evolution of its physical properties over time. That is why this study investigates the influence of accelerated aging on the properties of this material through a succession of immersion/drying cycles. Microscopic observations highlighted morphology changes of this bio-based material and porosity variations caused by swelling and shrinkage phenomena. A significant decrease of 51% in compressive strength was noted for the weathered hemp concrete. Furthermore, functional hygrothermal properties were also affected, and a 38% increase in water vapour permeability was noted. Finally, chemical and thermogravimetric analyses revealed no effect of aging on the pH and thermal decomposition ranges of hemp concrete. From these analyses, crucial conclusions on the durability of this material were drawn.