The objective of this study was cytological research of four Myxozoa species. We counted cell populations in plasmodium M. pseudodispar with the help of flow cytometry and detected 2 populations in early (103 cells plasmodium) and terminal (505 cells plasmodium) stages of infection, up to 5 cell types in the 104 cells plasmodium. We carried the analysis of organic and non-organic substances in the valves of live and stored water Heneguya oviperda and Myxobolus pseudodispar spores using cytochemical methods and atomic-absorptional spectroscopy and it shows the high content of Si (up to 94 %) and the presence of Ca, Mg, Fe, Mn cations (Cu, Al, Ni, Cr in fewer amounts) out. We investigated nuclei in plasmodium, spores of three Myxosporidia species Zschokkela nova, Myxidium gasterostei, M. pseudodispar using confocal laser scanning microscopy and compared DNA amount in Z. nova spores of myxo and actinosporidian phases of the life cycle. The features of the structure of nucleus and nucleosomal fibrils were found and described chromosomes in the nuclei of the generative cells of the same species.