In this work, we present a developed method for preconcentration of standards of proteins cytochrome c, myoglobin, and hemoglobin. Firstly, the electrolyte system was selected and optimized to provide low analysis time, narrow shape of the protein zone, and eliminate overheating at the center of the device. In the next step, the developed method was tested on the preconcentration of proteins: cytochrome c, myoglobin, and hemoglobin. After several adjustments myoglobin and hemoglobin were also uccessfully preconcentrated. After evaluation of pilot results, this technique provides up to fiftyfold preconcentration and recovery of over 70 % for each protein. The next plan is to preconcentrate proteins from complex biological matrices such as urine or blood plasma.