In this work a finite element simulation technique based on the molecular mechanics theory is developed to evaluate tensile properties of single-walled carbon nanotubes (SWCNTs). The fracture of carbon nanotubes is also studied by FE simulations. In the present modeling concept, individual carbon nanotube is simulated as a frame-like structure and the primary bonds between two nearest-neighboring atoms are treated as beam elements. The beam element properties are determined via the concept of energy equivalence between molecular dynamics and structural mechanics. The novelty of the model lies on the use of non-linear beam elements, to evaluate SWNTs mechanical properties and tensile failure. The calculated mechanical properties show good agreement with existing numerical and experimental results. © 2011 American Institute of Physics.