[en] The possibility of theoretical model calculation for prediction of isomeric cross-section was analyzed. The model calculations agree with experimental data quite reasonable in many cases. The agreement for threshold reactions at neutron energy 14 MeV is ∼20%. However, there are great disagreement between experimental and theoretical data in some cases. The reasons are: the lack of knowledge for lower levels schemes, γ-transitions between levels and spin's dependence of level density. There are the worse agreement for small isomeric ratio R<0.1. The simple formula to predict isomeric ratio for (n, γ) reaction was suggested. 20 refs.; 10 figs.; 3 tabs