The study proposes a Kansei Engineering methodology for the evaluation of customer impressions formed by the product information presenting a food supplement on e-commerce product pages. The study examined the design elements currently used for conveying information about the product in the unlimited digital space of online-sale product pages. The importance of product-page design was analyzed from the perspective of Packaging Design, Kansei Engineering, and Kansei Marketing. An evaluation of customer impressions of the information given about a certain food supplement (spirulina) on e-commerce product pages was performed. An identification of the most preferable product page, featuring different design elements and offering information about the product in textual, visual, visual/textual, and/or audio/visual forms, was carried out based on the users’ perceptions by the use of an emotional scale with product-page-specific Kansei words. The most preferable product-page presentation on an e-commerce product page, evoking positive customers’ perceptions and adding value to the product, was identified by multivariance analysis. The practical benefit of such evaluation is to elicit feedback from customers that can be used as guidelines to be considered and implemented by website owners and web designers at the early stages of the product-page design process.