The influence of an external electric field on a lysozyme solution has been analyzed with respect to protein concentration fluctuations and crystallization kinetics. The migration of lysozyme under an external electric field in a different media was investigated with a new device developed in the laboratory. The resulting diagrams show that an external electric field influences the protein concentration leading to a concentration gradient between the electrodes. The variation of the residual protein concentration during the crystallization process in the presence of an external electric field was studied at different salt and overall protein concentrations (in the range 0.4-1.5 M NaCl and 5-100 mg/ml lysozyme). At low ionic strength, the apparent residual protein concentration decreases more rapidly when the electric field is present.