We have performed a novel calculation of the “prompt” component of atmospheric leptons—muon neutrinos and muons arising in the decays of charmed particles. The same model of the hadron cascade is used in our calculation as in the calculation of the characteristics of “conventional” atmospheric neutrinos and muons (from the decays of π, K -mesons). The cross sections for the production of the charmed hadrons ( D , Λ c ) in pA and πA collisions are calculated within the quark–gluon string model (QGSM), whose parameters have taken into account recent measurements of cross sections of the charmed meson production at high energies. Zenith-angle distributions of the prompt muons and neutrinos have been obtained, the spectra of which are calculated as for certain zenith angles and averaged over zenith angles. The ranges of cross energy where the contribution of prompt leptons is comparable to fluxes of the (π, K ) muons and neutrinos are found. The possibility is shown to detect the prompt neutrinos from a combined analysis of the spectral characteristics and zenith-angle enhancement of two components of atmospheric neutrinos—(π, K ) component and prompt ( D , Λ c ) neutrinos in experiments at energies much lower than the cross energy.