The physical properties of real ZnSe crystals determine of their structures defects. This is a subject of many researches. In this work were investigated ZnSe and ZnS single–crystals, grown from the melt. Investigations of ESR spectra changes after plastic deformation are showing, that as against ZnS crystals, in ZnSe ones, the quantity of manganese impurity ions which are in twice ionized state depends of concentration of dislocations. Deformation of crystals decreases the quantity of Mn2+ ions. In spectra of manganese luminescence excitation there are not two maximums, which are corresponding to levels of upper excited states in ZnSе crystals. Such situation is possible if these levels are located in a conduction band. In this case they are detached from energy levels of a conduction band by high potential energy barriers. Electrons from levels of this upper excited states of manganese make tunnel transitions through barriers into conduction band and vice versa with equal probability. The part of Mn 2+ ions get into zone of action of electric fields of negatively charged of dislocations. The charge state of these Mn 2+ ions will be changed in result of preferred tunneling of electrons from levels of two upper excited states 4T2 ( 4G) and 4T1 ( 4 P) to conduction band. For testing this guess the action of dislocations was modeling by application to undeformed crystals of an external electric field. It turned out that effect of electric field is similar to effect of deformation. In crystals ZnS similar effects is absent. It is naturally so in these crystals all levels of excited states of manganese are located into forbidden energy gap and tunneling of electrons from them does not occur or more weak. It is interestingly that in ZnSе crystals in situ absentee maximums in spectrums of exciting we observed increase of a photoconduction.