Abstract: In this paper a magnetic sector mass spectrometer for experiments is described. Si-mulating test of the ion trajectory is carried out for ion optic system of the ion source.The chamber of magnetic analyzer is made of copper by means of electrotyping. A chan-nel electron multiplier is used for ion detection. Geometric parameters of ion optic systemof the magnetic analyzer are calculated. Resolution of the instrument is 380, Sensitivity is2×10~4 for strontinm sample.