Explicit formulas which describe muon pair production in reaction γν->μ + μ - ν through neutrino magnetic moment are obtained and used to derive in the leading approximation cross section of muon pair production in νN-scattering due to neutrino magnetic moment. This cross section appears to be proportional to log 4 E ν . Comparison with experimental data on tridents production provides an upper bound μ ν μ <4x10 - 8 μ B , which is approximately two orders of magnitude weaker than that from ν μ e elastic scattering data.