The agent for substitution of the blood plasma is made up of the vegetal protein substance edestin, advantageously a product from the hemp seeds. Advantageously, edestin is a component of the solution comprised of 5 % - 40 % in weight of edestin, 0.5 % - 7 % in weight of inorganic substances, 0.5 % - 7 % in weight of organic substances, hormones, and other substances to 100 % in weight of the colloid solution. According to the method of production of an agent for blood plasma substitution, the vegetal seeds are either cold-pressed or ground to powder and extracted under a compressed gas; the pressed out or extracted vegetal oil is separated, the pressed together or extracted seeds to be relieved of fat and decolorized are extracted by action of the organic solvents, the fat relieved and decolorized substance is then filtered out and exposed to action of the inorganic salts in the water solution and at the temperature from 20 DEG C to 60 DEG C, the solution is filtered and edestin is finally isolated from the filtrate. Advantageously, the hemp seeds are subjected to the cold pressing and grinding processes and to the gas-assisted pressure extraction. Advantageously, the vegetal seeds are being extracted under the compressed carbon dioxide.