We report here a new ternary solvated (perylene-TCNB)center dot 2THF cocrystal, which can transform into binary perylene-TCNB cocrystal reversibly by successive desorption or absorption of THF solvent. As a consequence, macroscopic mechanical bending would be realized when repeated stimulation with THF solvent. The present results clearly demonstrated that solvent induced mechanical bending is driven by structural change at the molecular scale. Such solvatomechanical bending behavior is clearly revealed for the first time.