Two essential functional requirements for electroactive artificial muscles, which can be used for biomedical active devices, are biocompatibility and sufficient range of motion. Fullerenol nanoparticles and their derivatives have been validated as potential candidates to be used for nanobiomaterials and biomedical applications because of their excellent proton conductivity, hydrophilicity, and biocompatibility. We developed fullerenol-based electroactive artificial muscles utilizing biocompatible polyetherimide. By using a solvent recasting method, present ionic networking membranes have been successfully synthesized with homogeneous dispersion of polyhydroxylated fullerene (PHF) nanoparticles into a sulfonated polyetherimide (SPEI) matrix. In comparison with pure SPEI membranes, the PHF-SPEI nanocomposite membranes show much higher water uptake and proton conductivity, which are both essential characteristics for high-performance ionic polymer actuators. The developed PHF-SPEI actuator shows over three times larger motion ranges and two times higher blocking forces than the pure SPEI actuator. The excellent biocompatibility of PHF and SPEI makes these actuators promising candidate materials for biomedical devices such as active stents and catheters.