The diffusion of electronics in everyday life requires for the development of sensing systems, based on new materials and technologies. Deformation sensors are of interest in many application fields, ranging from assisted rehabilitation, virtual reality and augmented reality, and gaming applications, juts to mention a few. The diffusion of low-cost sensing systems outlines the need for environmentally friendly and low-cost sensors. Cellulose is one of the most abundant materials on earth. Eventually, it is green, cheap, and flexible. In this article, the deformation sensing properties of a three-layer structure-based bacterial cellulose (BC) compound based on BC, impregnated by ionic liquids, and covered by conducting polymers are investigated. More specifically, it is shown that this novel composite is capable of sensing flexural deformations and producing a corresponding open-circuit voltage. The obtained results pave the road to the possibility of realizing a new class of deformation sensors that fit the requirements of more sustainable sensor technologies.