The invention provides a method for using a standard sample plate to quench a leaf spring and aims at significantly reducing the quantity of the sample plates of the leaf spring and cost for quenchingthe leaf springs with constant sections and improving the production efficiency. The method of the invention is characterized in that the length and the height of arc of the leaf springs with constant sections are aggregated, calculated and analyzed and the leaf springs with constant sections are classified according a certain length and then a plurality of standard sample plates are made according to a certain curvature interval of each category; when in quenching, the leaf springs with constant sections and the curvature in the interval, the standard sample plate with the most similar radius of the curvature is served as a quenching sample plate to quenching the leaf spring. As a result, the standard sample plates accounting for 1/40 to 1/20 of the current more than 8000 kinds of leaf springs with constant sections can successfully realize the quenching so as to simplify the making, management and maintenance of the sample plates and shorten the production period at the same time.