Sunflower is grown almost exclusively for the production of vegetable oil from its seeds. Sunflower stalks (or straw) are typically left on the field and have no market value. The pith from the stalks has been found to have insulation properties (both thermal and acoustic), and hence could play a role in the transition towards a low fossil-carbon economy. The goal of this study was to (i) produce sunflower straw-based panels and (ii) characterize their sound properties in order to (iii) assess their environmental performance by Life Cycle Assessement (LCA). Biobased sound absorption panels were produced from sunflower pith, using starch and chitosan as binding agents. By measuring the sound absorption coefficient in a Kundt's tube, the amount of panel required to provide a service of 1 m2 Sabin was estimated. Through a cradle-to-grave consequential LCA, the environmental performance of these panels was quantified and compared to a reference situation where straw is left unharvested, while sound absorption is supplied by conventional melamine foam. The end of life of the panels considers the crushing of the panels and their transportation and application back to the field; the analysis does include an assessment of the resulting changes induced on soil carbon dynamics. Sunflower pith panels proved to be more efficient than conventional melamine foam in terms of sound-absorption at low frequency ranges; the measured sound-absorption coefficients were almost 10 times higher. Harvesting and chitosan production were shown as hotspots undermining the environmental performance of sunflower pith panels. The LCA further revealed that pith panels production and use allows a better environmental performance than the reference situation for 6 out of the 9 environmental categories assessed, providing starch is used as a binding agent, and providing that harvesting technologies limiting the diesel consumption to maximum 30 L ha−1 are used to collect the stalks.