(57) An image-evaluating method comprising:

• (i) a step of forming plural lithographic printing plates for evaluation by subjecting image-forming materials comprising a support having provided thereon a light-sensitive layer containing both an alkaline aqueous solution-soluble resin and a compound which absorbs a light to generate heat, to exposure under a plurality of conditions with stepwise changing plate surface energy;
• (ii) a step of preserving the exposed plural lithographic printing plates for evaluation at a temperature of 15 to 23 °C;
• (iii) a step of developing at least one of the plural lithographic printing plates for evaluation with a standard developing solution having a standard formulation to prepare a lithographic printing plate having been treated with the standard developing solution;
• (iv) a step of developing other lithographic printing plates for evaluation than the above-described lithographic printing plate having been developed with the standard developing solution, with a developing solution to be evaluated according to the necessity of evaluation to thereby prepare lithographic printing plates having been treated with the developing solution to be evaluated; and
• (v) a step of comparing the state of image areas or non-image areas formed under predetermined exposure conditions in the lithographic printing plate having been treated with the standard developing solution with that in the lithographic printing plates having been treated with the developing solution to be evaluated.