Provided are: a cosmetic product that exhibits unprecedented innovative characteristics wherein ultraviolet protection effectiveness is not compromised by heat but rather gets enhanced upon exposure to heat； and a production method therefor. The present invention pertains to a method for producing a cosmetic product that provides enhanced ultraviolet protection effectiveness when exposed to heat, the method comprising: (1) a step for preparing a sample composition containing (A) an ultraviolet protection agent and (B) one or more moisturizing agents selected from among polyhydric alcohols and alkylene oxide derivatives having an IOB of at most 5.0； and step (2) for selecting a sample composition that has exhibited an improved protection effectiveness against ultraviolet after a heat treatment as compared to before the heat treatment, in accordance with an evaluation method comprising (i) a step for forming a coating film of the sample composition on a substrate, (ii) a step for performing heat treatment on the coating film formed of the sample composition, (iii) a step for obtaining measurements of the ultraviolet protection effectiveness of the coating film formed of the sample composition before and after undergoing a heat treatment, and (iv) a step for comparing the measurements of the ultraviolet protection effectiveness.L'invention concerne : un produit cosmétique qui présente des caractéristiques innovantes sans précédent, l'efficacité de protection contre les ultraviolets n'étant pas compromise par la chaleur mais étant plutôt améliorée lors de l'exposition à la chaleur ； et son procédé de production. La présente invention concerne un procédé de production d'un produit cosmétique qui fournit une efficacité de protection contre les ultraviolets améliorée lorsqu'il est exposé à la chaleur, le procédé comprenant : (1) une étape de préparation d'une composition d'échantillon contenant (A) un agent de protection contre les ultraviolets et (B) un ou plusieurs agent
