Aim and Background: In this study, Preparation and isolation of Iranian Mesobuthus eupeus venom toxic fractions has been performed. Its venom has different toxin same the other scorpions which affect on ion channels.

Materials and Methods: For studying of these toxins, the venom was isolated during 3 stages gel chromatography, DEAE anion and CM cation exchange chromatography respectively. At each stage, the fractions were identified with UV spectroscopy and collected with fraction collector then the fractions injected to 2 normal mice and the toxic fraction with killing effect selected for next stage.

Results: The results of injected fractions showed that the fractions F3, F31, F316 and F319 were toxic.

Conclusion: To determine the location of venom concentration in different organs can help to design proper antivenom.