Changes in resistivity of serpentine single-walled carbon nanotubes are presented as a function of bending radius, rb, in the range of 100–2000 nm. Resistivity (ρ) is observed to increase with curvature (1/rb), which is consistent with theoretical speculation on strain-induced bandgap increment. Furthermore, a sharp bend (rb < 50nm) in the nanotubes results in a drastic change in the field-effect behavior, i.e., from ambipolar to p type across the bend. Local Raman spectra show that the G-band Raman frequencies shift along the curvature, which may be attributed to local deformation and broken cylindrical symmetry in the nanotubes. The results suggest the possibility to tune the electrical properties by bending nanotubes and to build an all-nanotube device by modulating the structure of the same tube.