Theoretical uncertainties of the inclusive jet cross sections at the LHC experiments at 14 TeV

We have studied the theoretical uncertainties in the calculation of the inclusive jet cross section for the LHC experiments using the parton-parton NLO-generator JETRAD (2002) and the library of parton distribution functions LHApdf-5.3.1 for CTEQ65 and CTEQ6A. For beam energy $\sqrt{s} =1.96$ TeV the results are consistent with the original analysis, performed in CDF collaboration. For LHC beam energy $\sqrt{s} =14$ TeV the main theoretical uncertainties are associated with the dependence of the QCD factorization and renormalization scales (15%), with uncertainty of PDF (10%) and parton jet clustering uncertainty (3%).