Environment-friendly chemical nickel plating brightener and application thereof

The invention relates to an environment-friendly chemical nickel plating brightener. The brightener comprises one or more than one of rare earth lanthanum or lanthanum sulfate, tellurium dioxide or tellurium sulfate, bismuth chloride or bismuth nitrate or bismuth sulfate, sodium molybdate or molybdenum dioxide. The brightener contains no harmful substances such as lead or cadmium, has no toxicity or harm, is environment-friendly, and meets the European Union RoHS standard. The brightener is an ideal effective brightener which can substitute harmful substances such as lead and cadmium in current chemical nickel plating, has a brightening effect exceeding that of lead or cadmium brighteners. The brightener can obtain a plating layer which is dense, bright, and good in bonding force and corrosion resistance, and is easy to be plated on metal surfaces of copper, iron, aluminum, etc.