The aim of this study was to apply ohmic heating method to generate heat in seawater as an attempt to be utilized in desalination process as an alternative heating method rather than using steam boilers. The effects of temperature, electrical field strength and the concentrations of total dissolved solids (TDS) on electrical conductivity during ohmic heating of seawater were investigated. Heat was generated within the seawater using alternating electric current at frequency of 60 Hz, the range of electrical field strength was 6.35-11.04 (V/cm). Different concentrations of the seawater were prepared (range 38.9-106.1 PPT). Quality parameters include electrical conductivity, colour, pH, apparent specific heat and density of the seawater were measured at room temperature before and after the ohmic heating. The range of conductivity during ohmic heating was 55-399.6 (mS/cm) and strongly dependent on TDS and temperature. Ohmic heating can be applied for heating process of seawater with some limitations regarding the colour change. One major output of this research is the assessment of seawater electrical conductivity data during ohmic heating which adds a new perspective to system analysis, design and modeling of the potential use of ohmic heating to generate heat within the seawater during desalination process. (C) 2010 Elsevier B.V. All rights reserved.