TECHNOLOGY FOCUS - CHEMICAL ENGINEERING - Preferred Apparatus: The electrolyte solution is filled in an electrolyzer (21). The electrolyzer and metal electrode (23,24) disposed in the electrolyzer are combined to form hydrogen generating apparatus (20). The electrode (23) is immersed in the electrolyte solution, and generates electrons. The electrode (24) is immersed in the electrolyte solution, and generates hydrogen gas by receiving the electrons. The electrolyzer further comprises a container for holding the cation exchange resin. The container has a main body frame having hole(s) for placing the cation exchange resin, and shield frames attached to the lateral side of the main frame. The shield frame is combined with a mesh to cover the shield frame. The cation exchange resin is coated on the inner wall surface of the electrolyzer to be in contact with the water. The electrode (23) comprises magnesium. The hydrogen generating apparatus is combined with a fuel cell to supply hydrogen to the fuel cell.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Compound: The ionizing compound is chosen from lithium chloride, potassium chloride, sodium chloride, calcium chloride, potassium nitrate, sodium nitrate, potassium sulfate and/or sodium sulfate.    TECHNOLOGY FOCUS - POLYMERS - Preferred Resin: The cation exchange resin is a polymer resin having a cation exchange group chosen from sulfonic acid group, carboxylic acid group, phosphoric acid group and phosphonic acid group, preferably chosen from styrenic strongly acidic cation exchange resin with sulfonic acid group, styrenic weakly acidic cation exchange resin with carboxylic group and/or acrylic weakly acidic cation exchange resin with carboxylic group. The styrenic strongly acidic cation exchange resin is a styrene-divinylbenzene copolymer with sulfonic acid group. Preferred Composition: The content of cation exchange resin is 20-40 wt.% with respect to total weight of electrolyte solution. Preferred Property: The cation exchange resin has particle size of 1-0.4 mm. EXAMPLE - Potassium chloride (in wt.%) (30) and Amberjet 1500H (RTM: styrene-divinylbenzene copolymer having particle size of 1 mm) (20) were mixed to obtain an electrolyte. The obtained electrolyte, a metal electrode made of magnesium and another metal electrode made of stainless steel were combined to form hydrogen generating apparatus. Electrochemical reaction was carried out, and hydrogen was generated. The hydrogen generation (32 cc/minute) lasting time was measured as 140 minutes.