We present the fresults of the investigation of the effect of notches on the brittle-ductile transition in the process of fracture of structural materials. It is shown that the local elastoplastic state of a material in the vicinity of the notch can be described by using the corresponding stress intensity factorsK I σ , strain intensity factorsK i e , and strain-energy intensity factorsK I ω . We prove that the factorsK I σ andK I e are linear functions of the notch radius ρ on the\(I/K_I^i - \sqrt \rho \) coordinates (wherei=σ or e) and propose to characterize the brittle-ductile transition in the process of fracture of the material by the slopes of these functions.