Dynamically identifying key product changes is a challenge for enterprises. It is even more complicated if companies strive for the sustainable development of their activities. Therefore, the aim of the article was to develop a method to help predict the direction of product improvement, taking into account its quality level and environmental impact during the life cycle (LCA). The method was based on the design phase of LCA and the process of obtaining and processing customer expectations. Techniques supporting the developed method were: a questionnaire, a seven-point Likert scale, a standardised list of criteria for assessing the product life cycle, the WSM method, and a scale of relative states. The product analysis was carried out according to modified criteria states, which were evaluated according to: i) customer satisfaction (quality criteria), ii) environmental impact of LCA (environmental criteria), and iii) importance of quality and environmental criteria for customers. The originality of the method is to support the product improvement process to make it environmentally friendly within LCA and, at the same time, satisfactory to customers in terms of quality. The method will be used mainly by SMEs that want to initially predict the environmental impact of a product, including taking into account customer expectations.