The mechanical, thermal and electronic properties of the nanoscale materials are studied using an ab initio molecular dynamics (TBMD) method and statistical moment method. We investigate the strength and fracture behaviors of nanoscale materials like carbon nanotubes (CNT), graphens and nanowires in comparison with those of corresponding bulk materials. The thermal lattice expansion coefficients, linear elastic parameters, nonlinear elastic instabilities and bucking, inelastic relaxation, yield strength and fracture behaviors are studied in detail, including the anharmonicity of thermal lattice vibrations. We will show that the thermodynamic and strength properties of the nanoscale materials are quite different from those of the corresponding bulk materials. The electronic density of states and electronic transports of the nanoscale materials, with and without the atomistic defects are also discussed.