Abstract: The combination of conductive carbon nanotubes (CNTs) and non-conductive flax fibers (CEL) can produce flexible conductive composites. Stretching or bending the material greatly affects its electrical conductivity. According to the resistance change rate(ΔR/R₀), the change in the shape of the material can be sensitively detected, so the material is suitable for deformation sensors. The flax fiber pulp was obtained using sodium hydroxide/urea water system to treat flax fibers, which is then mixed with different concentrations CNTs suspensions, filtered, and dried to prepare conductive CNTs/CEL composite. The structure and morphology of the CNTs/CEL composites were evaluated withXRD, FTIR and SEM. The CNTs/CEL composite materials were made into deformation sensors, and the tensile conductivity was used to test the effect of stretching on the conductivity of the sensors; the optimized sensor was used to monitor the finger joints bent movement on the bases of the resistance change to test the deformation sensitivity of the sensor. The results show that with the increase of tensile strain, ΔR/R₀ of CNTs/CEL sensor increases gradually. Under 50% strain, ΔR/R₀ reaches over 980 and could be sensitively sensed shape changes. As the degree of bending of the finger joint increases, the resistance of the CNTs/CEL sensor increases as well. When the finger is bent to the greatest extent, the resistance of the CNTs/CEL sensor can reach more than 12000 Ω, and the repeatability is good.