Abstract: The Laboratory tests have demonstrated that, optical microscopic can be an alternative method for characterization of water-in-oil (w/o) emulsions. The 50-50% w/o emulsion was prepared and decolorized by adsorbing in fumed silica to remove its black color. Factors such as stirring speed, emulsification temperature and their effects on emulsion viscosity and droplets size have investigated. Results showed that emulsion viscosity and stability were increased by increasing agitation speed and decreasing temperature, while droplets size decreased with increasing agitation speed.