Structure of isomer-separated crystalline C-82 has been studied by powder x-ray diffraction with synchrotron radiation. The Rietveld refinement was achieved by assuming a simple cubic lattice (space group Pa (3) over bar). The C-2(a) symmetry for the C-82 molecule was supported in this analysis. Transport properties of thin film of C-82 have been studied by resistivity measurement. The thin film showed a narrow-gap semiconductorlike behavior with gap energy of 0.43 eV. The field effect transistor (FET) of a C-82 thin film showed an n-channel normally-on depletion-type behavior, and the mobility was 1.9x10(-3) cm(2) V-1 s(-1) whose value was one of the largest mu among normally-on FETs with fullerenes. A hopping transport was found as channel conduction for the C-82 FET above 150 K.