The self-contained portable device for filling cylinders with high-pressure hydrogen comprising a reaction chamber containing a solid reagent cartridge and reaction liquid pipe configured to supply liquid reagent to the lower part of the reaction chamber, a refrigerant dryer comprising installed in series a hydrogen cooler, filter-separator and hydrogen dryer, liquid reagent pipeline connected with the reaction liquid pipe, high-pressure hand pump connected with the liquid reagent pipeline to the reaction chamber and configured to feed liquid reagent in portions to the reaction chamber, gaseous hydrogen pipeline connecting the reaction chamber and refrigerant dryer, treated gaseous hydrogen pipeline configured to supply high-pressure hydrogen from the refrigerant dryer to a cylinder, wherein the gaseous hydrogen pipeline, treated gaseous hydrogen pipeline and liquid reagent pipeline are equipped with quick-release couplings, and the reaction chamber is placed in the reaction chamber cooling tank.